ALBERT

Description: It has been shown that dried sugar-beet pulp contains a high percentage of pectose. A number of successive digestions of 1 hour each with 0·5 per cent. ammonium oxalate at 100° C. extracts an amount of pectin equal to 34·5 per cent. of the weight of dried beet pulp, basing the determination on the weight of crude pectin precipitated when the extracts are run into 95 per cent. alcohol. A single prolonged digestion gives a yield of crude pectin equal to 32·2 per cent. of the dried beet pulp.Digestion with acidic reagents, such as 0·5 per cent. oxalic acid, 0·6 per cent. tartaric acid, N/20 hydrochloric acid, etc., leads to a quicker extraction of pectin, owing to a speeding up of the pectose to pectin hydrolysis. The yield of pectin, however, is not thereby necessarily enhanced, since under such conditions the pectin undergoes a slow secondary hydrolysis during the extraction with the formation of reducing substances not precipitated by alcohol.Prolonged digestion at 100· C. of dried sugar-beet pulp with water alone also leads to a satisfactory extraction of pectin.

Description: (1) The desiderata of a sampling-method are outlined, and the particular case of sampling a large number of potato plots discussed.(2) An analysis is made of the yields of 54 sub-plots of the Rothamsted Potato Experiment of 1928, both as estimated by a sampling-method and as determined by large-scale lifting.(3) It is shown that most of the significant results of the experiment are obtained from the sample-yields, but that the higher standard error per plot obscures the effect of superphosphate.(4) It is concluded that at Rothamsted 102, and at Woburn 56, plants would have to be lifted to give a sampling-error as small as 4 per cent. It would then be profitable only to sample experimental plots of 1/20th acre or more in area.Finally it is a pleasure to record our indebtedness to Dr R. A. Fisher for much valuable advice and criticism: and to Mr H. J. G. Hines for assistance with the field work.

Description: The last issue of this Journal (p. 132) contains a paper by Dr R. A. Fisher on the effect of Silica upon the growth of Barley at Rothamsted, which begins by stating that his data “show conclusively that the view previously rejected that the silicate acts by making available to the plant the actual reserves of soil phosphates must be regarded as strongly established.” Twice elsewhere Dr Fisher states that this erroneous conclusion of previous investigators is due to the fact that they had considered only the proportion of phosphoric acid in the ash and had overlooked the increase in the total phosphoric acid in the crop. As Mr Morison and I were the previous investigators in question I turned to our twenty-three-year-old paper with some curiosity to ascertain the grounds for this magisterial dismissal of our conclusions, for my remembrance of the subject did not tally with the opinion Dr Fisher attributes to us. Still less do I agree now that I have re-examined our original paper.

Description: An account has been given of an investigation into the seasonal changes in the productivity, botanical and chemical composition, and nutritive value of pasture grass, the work constituting the initial stage of a comprehensive study of the nutritive properties of different types of pasture. The pasture on which the work was carried out was situated on a light sandy soil of low water-retaining capacity; the pasturage was of medium quality.Grazing was imitated by the daily use of a motor-mowing machine, the system of cutting being such as to ensure the whole plot being cut over once per week. The season was divided into ten periods, each period corresponding with the duration of a digestion trial carried out on two wether sheep. The main feature of the weather conditions during the season was the extremely low rainfall during the period from early June to mid-July.The pasture plot results were compared with corresponding results obtained from contiguous plots which were allowed to grow for hay, and from which, after removal of hay, several successive aftermath cuts were taken. The main findings of the investigation are summarised below:Seasonal changes in the botanical composition of the herbage. Although precise and systematic botanical analyses of the herbage of the pasture were not carried out, yet careful surveys made at an early and a late date in the season, together with general observations made during the whole course of the experiment, enabled interesting conclusions to be drawn in respect of the seasonal activity and persistency of the different species of grasses in the sward. During the spring season, Bromus mollis, Lolium perenne, Poa annua and Poa trivialis accounted for almost 80 per cent, of the herbage.

Description: (1) The addition of basic slag to moist base-unsaturated soils, under laboratory conditions, causes an increase in their content of exchangeable calcium, degree of saturation, pH, and the amount of calcium soluble in an aqueous solution of carbon dioxide.(2) Slag seems to be almost as effective as calcium carbonate or lime in increasing the exchangeable calcium and the degree of saturation of soils, but its action on pH is not so marked.(3) The effect of dressings of slag on the lime status of soils from experimental plots is still evident after eight years.(4) The exchangeable calcium of samples of soil taken from the same fields after an interval of six years shows a considerable fall due to leaching.(5) It is suggested that the addition of low grade basic slag to unsaturated soils may tend to maintain or improve their lime status and will, to some extent, compensate for the loss of calcium due to drainage and crops.

Description: The addition of aluminium salts to culture solutions and to soils will bring about certain changes; these may be summed up as follows:1. A change in the hydrogen ion concentration, which will vary in amount with the original buffer properties of the solution or the soil.2. A change in the buffer properties of the solution or the soil; the hydrogen in concentration of a culture solution containing an aluminium salt will tend to remain more constant than that of a normal culture solution during the period of growth of the plant, when both start at the same pH value.3. Precipitation of soluble phosphate as aluminium phosphate except in solutions or soils more acid than pH 3·5 to 4·0; this might lead to phosphate starvation in water cultures but would have little or no effect in a soil, where the particles would remain accessible to the plant roots.

Description: Some recent researches on the evaporation of water from soil are reviewed.Experiments on the evaporation of water from a soil paste spread in shallow pans showed that the drying proceeded very irregularly over the soil mass. Considerable portions became almost completely dry whilst other portions remained very wet. There was a rough relationship between the form of the dry patch and the shape of the corresponding evaporation rate curves.An improvement in technique was effected by exposing the soil in thin layers below glass plates. Under these conditions, reproducible results were obtained. Soil and kaolin, but not sand, gave considerable linear portions over the region of decreasing rate of evaporation. Tests on soil exposed as central discs, or peripheral rings, and on partially covered full plates, showed that, owing to the type of air currents set up, the drying was largely confined to the outer edges during the early stages.

Description: The question of the composition of sugar beet tops and their utilisation for feeding purposes has been dealt with in a recent publication (l). The purpose of the present communication is to record the results of investigations into the problem of the preservation of sugar beet tops by the method of ensilage. The account falls naturally under four headings:I. Ensilage of sugar beet tops alone.II. Ensilage of sugar beet tops mixed with wheat chaff.III. Ensilage of sugar beet tops mixed with wet sugar beet pulp.IV. Nutritive value, as determined by digestion trials on sheep, of the silage obtained from the mixture of tops and pulp.

Description: The figures analysed in the subsequent pages were obtained (by the kind permission and help of Prof. S. Pennington) during the five years, May 1920 to May 1925, from the College Farm dairy cows at University College, Reading, and before proceeding, a few notes on the herd and its management are desirable.The herd is small (14–18 animals), and was established in 1908 by purchasing non-pedigree Dairy Shorthorn heifers which have since been “graded up” by the use of Pedigree Dairy Shorthorn bulls. The cows are typical Dairy Shorthorns, of a fairly large size, and the degree of fatness normally maintained might be described as good thriving condition, and probably better condition than average dairy cows.

Description: The calcium arsenate-lime-lime sulphur spray has been studied in the laboratory and from the results so obtained it is inferred(1) That the formation of a stable tricalcium arsenate by precipitation from aqueous solution is improbable. The interaction of calcium hydroxide and dicalcium arsenate results in the formation of a continuous series of basic calcium arsenates which are hydrolysed in aqueous suspension.(2) That through the formation of such basic calcium arsenates the addition of lime to dicalcium arsenate reduces the amount of arsenic in solution. This reduction is temporary and on exposure to atmospheric carbon dioxide the original solubility of the dicalcium arsenate is restored. The concentration of soluble arsenic in the dicalcium arsenatelime spray will not be as great as in the dicalcium arsenate spray and the risk of spray injury with the dicalcium arsenate spray is therefore reduced when lime is added.(3) The concentration of soluble arsenic in the dicalcium arsenate and lime spray is reduced by the admixture of lime sulphur with a corresponding reduction of the risk of foliage injury.(4) The precipitation of sulphur from the calcium polysulphides of the lime sulphur is unaffected by the addition of dicalcium arsenate. The addition of lime may result in a diminution of the amount of sulphur so precipitated but such a reaction is dependent on the rate of carbonation of the free lime on the leaf surface. The fungicidal activity due to the calcium polysulphides is therefore unaffected by the addition of dicalcium arsenate but may be adversely influenced if excess of calcium hydroxide be present.

Description: In the Journal of Agricultural Science for October 1921, Dr J. W. Capstick described a calorimeter large enough to take a full-grown pig or a small bullock. This apparatus was in regular use up to the end of 1923 and proved, on the whole, quite satisfactory.

Description: The investigations described in the present paper are based on the records of the dairy herd at the farm of the University College of North Wales, at Aber near Bangor. The results obtained will have a more definite significance if some account is given of the nature and management of that herd.The Bangor provincial area, including the four Northern Counties of Wales, is roughly divided into Welsh Black and Shorthorn country by the Conway River. Most of the cattle in Anglesey and Caernarvonshire are of Welsh Black type, and the ordinary non-pedigree dual purpose type of Shorthorn predominates in Denbighshire and Flintshire.

Description: 1. Tubers obtained from secondary leaf-roll plants have a lower dry matter content than tubers from healthy plants. The percentage of nitrogen in the dry matter is appreciably higher in the former than in the latter. The difference in dry matter content is sufficiently large in many varieties to characterise leaf-roll tubers. Seventeen varieties were examined.2. The rate at which the nutrient materials are removed by the young plants from leaf-roll mother tubers is much slower than in the case of plants from healthy mother tubers. This may be a cause of the stunting characteristic of leaf-roll plants.3. When there is any doubt as to the diagnosis of secondary leaf-roll by the usual symptoms, a determination of the dry matter in the mother tuber two to three months after planting, would serve as a further diagnostic character.

Description: 1. A thermophilic organism which destroys cellulose at 65° C. has been isolated in pure culture.2. The organism is motile, gram negative, forms spores in the swollen end, stains well with carbol fuchsin, poorly with methylene blue.3. After growth on media without cellulose the organism is unable to ferment cellulose.4. The range of fermentation is from 43° C. to 65° C. The organism lives at 38° C. and 72° C. but does not ferment at these temperatures.5. The spores are very resistant to heat and withstand 115° C. for 35 minutes.6. Heating the spores to 100° C. for 5 to 10 minutes causes an increased rate of germination.7. Carbohydrates fermented: cellulose, starch, raffinose, sucrose, maltose, lactose, mannose, galactose, fructose, glucose, xylose and arabinose.8. Organic nitrogen is necessary for the fermentation, and peptone is the best source.9. The products from cellulose are: acetic acid, small amounts of butyric acid, ethyl alcohol, carbon dioxide and hydrogen. The amount of cellulose destroyed in a 1 to 5 per cent, suspension varies from 70 to 95 per cent. Of the cellulose destroyed, 50 to 55 per cent, is regained as acetic acid, 5 to 25 per cent. as ethyl alcohol and the rest as small amounts of butyric acid, carbon dioxide, hydrogen, and pigment. The pigment is a fatty substance soluble in ether.

Description: During the past five years many appeals for assistance have been received at this Institute from cheesemakers in various parts of the country, who from time to time have found, themselves unable to secure satisfactory coagulation of their milk by rennet by reason of some abnormality which is not patent to the eye.Difficulties are also encountered in the liquid milk trade from causes which appear to resemble those which trouble the cheesemaker.In view of the necessity for detecting milk such as this, use has been made of di-brom-ortho-cresol-sulphon-phthalein or brom cresol purple, which indicates colorimetrically the reaction or hydrogen-ion concentration of milk, and provides a starting point for the further investigation of those samples of which the reaction is abnormal.

Description: The mechanism by which viscogen (calcium saccharate) brings about an increase in the viscosities of milk and cream has been investigated.The primary reaction appears to be the formation of a precipitate of insoluble (tri-calcium) phosphate. Considerable quantities of casein are carried down by the precipitate, and this co-precipitation of casein is probably the single factor which most influences the viscosity.Casein is not directly precipitated by viscogen, but the viscosity of its solutions is slightly increased as a result of their higher alkalinity due to this reagent. This action of viscogen is relatively unimportant in influencing the viscosity of milk or cream.

Description: Herd statistics of cattle in India suggest that for animals of about 3500 lb. yield capacity a calving interval of rather less than a year will give the best results in the following lactation. For cattle whose yield capacity is 6000 lb. an interval of 420 days is desirable while one of less than 335 days is seriously injurious.Study of individual cows and their recorded histories reinforces the above conclusions and also suggests that the interval should be longer in early lactations than in late and progressively longer as the milking capacity increases.It also indicates that unrestricted access to the bull may prevent the real yield capacity of a cow being discovered.

Description: 1. In pot experiments with Glycine hispida and Vicia faba L., fresh chaff incorporated with the soil caused a significant increase in the number of nodules produced on inoculated plants, this increase being augmented by the further addition of phosphates.2. Fresh chaff, added at the time of sowing and inoculation, had more effect than chaff which was allowed to decompose in the soil for a month.3. Fresh chaff increases the multiplication of the nodule organism in sterilised soil.4. In soy beans without nodules, the chaff depressed the growth of the tops, but this depression did not occur either with soy or broad beans where nodules were present.5. In a field experiment made at Rothamsted, chaff, freshly ploughed in, increased the growth of broad beans and also of wheat sown the next season on the same ground.

Description: In the first paper of this series (10)1, Keen and the present writer discussed work by earlier authors on the approximate specification of the nature of a soil by a single soil constant, in place of a detailed analysis, and described experimental work designed to show the significance of a number of simple physical measurements. The chief objects of the present paper are to describe the results obtained with such measurements as applied to a number of Natal soils, and to discuss the value of some other easily obtained physical data as a means of specifying the nature of a soil. Work of this type was discussed at the International Congress of Soil Science at Washington in 1927, and it was resolved that co-operative work on an international basis should be undertaken.

Description: 1. Cereal plots were sampled by three different methods; two systematic, and one involving a random location of sampling units.2. The disadvantages of the systematic methods as compared with random sampling, emerged clearly.3. These disadvantages were further emphasised in an analysis of earlier data on sampling methods. For this purpose the methods and. results of certain recent contributions to statistical theory were used.4. By the use of a random sampling method, the variance due to sampling errors may be made a satisfactorily small fraction of the total variance of cereal plots one-fortieth of an acre in area.

Description: 1. The nature of the replaceable base in a clay or soil exerts a profound effect on the physical properties. Clay-like properties are exhibited most strongly in the case of lithium, sodium, and magnesium.2. The proportion of fine material in a soil (i.e. that which remains in suspension in a column 10 cm. high after 14 days) cannot be correlated with other physical properties. Thus a soil of which over 50 per cent, was dispersed to this extent was the least plastic of those examined.3. A comparison of sodium, potassium, and calcium clays and soil showed that potassium resembles sodium in its chemical relationships as indicated by base exchange, but is very different from it in such physical properties as plasticity and permeability.4. Using mixtures of one-half normal chlorides of two bases, calcium and potassium are absorbed in equivalent amount while the sodium absorbed is only one-sixth of the amount of either of the other two.

Description: The cobaltinitrite method, in the volumetric form here described in detail, enables known amounts of potassium to be accounted for quantitatively, independently of the presence of alkaline earth sulphates, or phosphates, provided that the amount of potassium is not varied over too great a range. The factor 0·000830 gm. K2O per c.c. N/10 KMnO4 suits the procedure described over a range of about 3 to 50 mg. K2O. Outside this range, or for highly accurate work within it, it may be desirable to calibrate the method.The method may be applied, in plant-ash analyses, indifferently to the original extracts containing other bases and phosphates, or to the mixed sulphates weighed for sodium and potassium together. It is applicable to small-quantity work upon soils with greater exactness and speed than is the perchlorate method. Citric acid extracts can be handled, with a relatively short manipulation, to give satisfactory results.Some analyses of ammonium chloride extracts have been unsatisfactory, and attention is called to the desirability of setting exchangeable potassium determinations upon a firmer analytical basis, by investigation of methods of freeing the extracts from ammonium salts.

Description: Though it is neither customary nor perhaps desirable to utilise sugar beet for feeding purposes, it is conceivable that circumstances might arise occasionally when a farmer would be desirous of feeding the whole or part of his beet crop. This is indicated by the fact that enquiries as to the value of sugar beet for pigs are received from time to time. During the carrying out of the investigation into the value for pigs of dried sugar-beet pulp and molasses-sugar beet pulp, an account of which work is given in this issue of the Journal (1), the opportunity was taken of making a similar study of whole sugar beet. A dual investigation was made, consisting of a digestion trial under the conditions of the metabolism room and a large-scale feeding trial under ordinary farm conditions. It was hoped that the evidence from this twofold line of enquiry would not only settle the question of the value of sugar beet in the feeding of pigs, but also throw light on the subject of the value of root crops in general for swine.

Description: The severe climatic conditions under which cotton is grown in the Gezira make it desirable to establish relations between meteorological data and irrigation practice. By means of a rapid and fairly accurate balance it is practicable to measure water loss when small boxes containing moist soil are exposed for short periods and under different conditions. The scope of this method has been ascertained by preliminary experiments as to (1) the dependence of water loss on moisture content of the soil, (2) the distribution of water loss through the day, (3) the comparison of water loss from sand and from. Gezira soil, and (4) the comparison of water loss from shaded and unshaded soil. The application of data so obtained to field problems is facilitated by the fact that in respect to distribution and amount losses from soil are related to loss shown by a Piché evaporimeter. Within the canalised area alternation of irrigated and fallow land is responsible for local variations in atmospheric conditions. A daily fluctuation in the moisture content of surface soil from fallow land is recorded and may be instrumental in favourably modifying its physical properties. The heat of wetting of Gezira soil has been measured.

Description: (1) The mineralogical composition of the fine sand fraction of certain soils from the south-east of Scotland is described.(2) The soils are shown to possess a fairly high content of silicate minerals in a comparatively fresh state.(3) The distribution and amount of potash, phosphate and lime-bearing minerals in the soils is discussed.(4) The soils can be grouped according to their mineral content and this grouping is found to depend on the geology of the parent material.(5) All the soils are formed on glacial drift and the results suggest that the local rocks have a preponderating influence on the composition of the matrix of the drift.

Description: (1) In absence of decomposing organic matter addition of nitrate led to no loss of nitrogen.(2) On addition of small quantities of fermentable matter such as glucose there was (a) rapid depletion of nitrates and oxygen, but no denitrification, and (b) increase in acidity, carbon dioxide and bacteria. The greater part of the soluble nitrogen was assimilated by microorganisms or otherwise converted and the greater part of the added carbohydrate was transformed into lactic, acetic and butyric acids.(3) The organic acids were formed from a variety of carbohydrates. Lactic acid was the first to be observed and appeared to be formed mainly by direct splitting of the sugar. It decomposed readily, forming acetic and butyric acids. Some acetic acid was formed by direct oxidation of lactic acid, with pyruvic acid as the intermediate product. All the acids were, on standing, converted into other forms by micro-organisms.

Description: (1) Soil surveys are classified into (i) preliminary reconnaissance surveys, (ii) broad ecological surveys, (iii) detailed physiological-ecological surveys, and (iv) special-purposes surveys. The objects of each are briefly discussed.(2) Particular consideration is given to the methods of physiological ecology, which attempt to assess the chief soil factors controlling plant growth.(3) Soil factors are grouped into (A) static factors, which do not fluctuate appreciably during a growing season, and (B) dynamic factors that may exhibit marked fluctuations within a season, or during years when climatic conditions vary.

Description: The conclusions of the 1927 experiments in spacing have been tested in greater detail in 1928 and are confirmed.From the 64-plot scheme containing a series of spacings in quadruplicate the following points emerged:(1) Variation of the width between the rows influenced the yields of sugar beet roots, the expectation of highest yield being on the narrowest spacings. There was a significant increase in yield to be gained by using 15” or 18” spacing instead of 21” or 24”. On the other hand width between the rows did not seem to influence the yield of tops and crowns.(2) Variation of the distance between plants in the rows up to 10” had no significant effect on the yield of roots. There was some evidence that above that figure a reduction in yield took place. It is interesting to note that in the case of the tops, spacing between the plants influenced the tonnage. There was a significant difference between the yields on the 4″ and 8″, and 4″ and 10″, but not between the 4″ and 6″, 6″ and 8″ or 8″ and 10″ spacings.

Description: The results of an investigation into the utilisation of sugar-beet pulp by ruminant animals were brought forward in a recent publication (I). It was demonstrated that sugar-beet pulp is highly digestible when consumed by ruminants. In respect of the digestibility of its N-free extractives and total organic matter, it compares very satisfactorily with maize meal. The process of drying the wet beet pulp in the factory does not depress its digestibility. Further, from the standpoint of digestibility, it is immaterial whether sugar-beet pulp is included in the rations of ruminants in the dry or the soaked condition. When, however, liberal allowances of the dried product are being fed to animals, it is desirable that the food should be well softened in water before feeding. This procedure ensures a higher availability of the digestible nutrients for productive purposes in the animal and also averts risk of choking trouble which sometimes arises, especially with sheep and lambs, during consumption of the dried beet pulp.

Description: Very considerable amounts of money are annually expended in Mauritius for the purchase of artificial fertilisers, and consequently it is of importance to know what happens to these substances when they are added to the soil. Extensive laboratory experiments have been carried out with nitrogenous fertilisers(1, 2), and also with phosphatic manures(3), and in order to complete the series an investigation into the availability of potash when applied in various forms was undertaken. Local practice favours the use of potash chiefly in the form of nitrate of potash and molasses, and on this account the availability of the potassium oxide in these two substances was tested, and in addition, in potassium sulphate.

Description: (1) A large series of data on the duration of gestation in the goat has been analysed and the constants calculated.(2) The frequency curve is unimodal and symmetrical, suggesting a single factor or a variety of factors acting simultaneously as the cause for birth.(3) Slight breed differences exist in the duration of gestation in the goat as in other species examined.(4) There is a continuous variation in the duration of gestation with the time of year at which conception occurs. Spring conceptions give shorter gestations than autumn conceptions.(5) There is a distinct difference in the duration of gestation for young and older dams. This is related to the age of the dams and not to the order of the births. Gestation is shorter in the young animal than in the older.(6) In the goat the size of litter has little or no effect on the duration of gestation.(7) Constants for duration of gestation in other species have been obtained. Variability increases with the duration of oestrus and about half the variability in any species with a long oestrous period may be ascribed to this cause.(8) The factors involved in fixing the duration of gestation in the species examined are evidently the same in all cases, and probably culminate in a single agency responsible for terminating gestation.

Description: A series of upwards of 6000 matings of goats has been arranged according t o the month of service and correlated with temperature and rainfall.The maximum of reproduction is found to be in October, and the minimum in May.A cool summer produces early oestrus while a hot one has the opposite effect. The August temperature is of paramount importance in this respect.Rainfall had no effect, on the onset of oestrus in the series examined.The hypothesis is advanced that most mammals breed only in the spring and autumn because their body temperature may be too high in summer for follicular development.

Description: For the purposes of this article the “food capacity” is taken to be the amount of total dry matter consumed when the animal is offered as much as it cares to eat. This has been estimated from the results of a variety of experiments collected by the author for the purpose.The evidence quoted shows that the food capacity of steers is subject to a nearly uniform acceleration of 40 lb. per month per month from birth up to the age of 12 or 14 months, after which it remains approximately constant. It cannot therefore bear any simple relation to the live weight of the animal.In the case of steers the average constant rate of consumption was about 18 lb. of total dry matter, per head, per day, throughout the period from 1 to 4 years of age; in the case of milk cows it is probably about twice as great, viz. from 30 to 40 lb.The food capacity of steers has been much exaggerated by various scientific writers. In Kellner's tables it seems to be implied that the capacity varies as the live weight and that it may be as much as 64 lb. per head per day, i.e. 3½ times as much as was found in the experiments under review.

Description: The flooding with sea-water of land around the Humber in 1921 spoilt a considerable area of arable land.The effects of the flooding, which consisted chiefly in an entire destruction of the tilth of the soil, are described, and compared with the recorded effects of similar floods in Holland and in Essex.The results of an examination of the exchangeable bases in the flooded soil are considered in the light of modern work on the relation between the nature of the exchangeable bases in the soil and its physical condition. It is shown that the observed effects can be explained by replacement of a considerable proportion of the exchangeable calcium of the soil by sodium.Dutch experience on the reclamation of flooded soils is discussed. It is shown that in the first few years after flooding the land should be cultivated as little as possible.The use of lime or gypsum for the treatment of flooded soils, in order to hasten the restitution of calcium to the clay in place of sodium, is discussed. From an examination of the soil from plots which had been treated with these materials it is shown that although both produced in some degree the desired effect chemically, the action did not proceed far enough in 12 months to produce a noticeable improvement in the tilth.It may be possible under favourable conditions to grow certain arable crops on flooded land, among which crucifers appear to be specially suitable.However, the most satisfactory and promising means of hastening the recovery of tilth and fertility by flooded land appears to be the establishment of a ley of lucerne, clover, or “seeds” which can be left down for several years.

Description: Two sets of records, for Light and Heavy Horses respectively, have been analysed statistically, with the object of studying some of the factors which affect the percentage of foals left by a stallion in a service season.It has been found that the stallion himself is one factor, in that each individual’s percentage returns, in successive seasons, tend towards a constant figure; although there is every gradation, and even considerable variation from year to year, there are definitely good and bad “getters” of foals.A stallion's fertility varies according to the district of the country in which he stands or travels, being higher in the north and west of England and Wales than in the south and east, and very low in Scotland.In moderation, frequent use does not impair a stallion's fertility; there is, in fact, some (insignificant) evidence that the more mares he serves, the greater the proportion of foals he leaves.There is a slight tendency for a stallion's fertility to rise from the time he is 3 years old till he is 13 years old—this result may, though, easily be due to chance; on the other hand it is quite clear that fertility declines after the age of 16 years, and this occurs over the whole range, and is not caused by a certain number becoming absolutely sterile.

Description: Although the infertility of the subsoil in humid, semi-arid and arid regions has received much attention from investigators in Europe and America, in South Africa, as far as the writer is aware, no such work has been done.

Description: A physical form of “ropiness” in milk has been described and shown to be due to the formation of thin films of casein and (or) lactalbumin at the milk-air interface.The “ropes” are a form of the “mechanical surface aggregates” of Ramsden and may occur on appropriate surfaces, such as ordinary farm coolers whenever the rate of flow, the temperature and the acidity conditions are favourable.A modification of Ramsden’s method demonstrating the formation of mechanical surface aggregates, in an hitherto unobserved form, has been described, viz. horizontal glass tubes in parallel which are especially suitable for opaque fluids.The condition appears to be identical with that described by Aekma and Brouwer(2) who showed the occurrence of corpuscles in milk after violent agitation. These corpuscles probably consist of thin films of solid protein which as in the cases described by the author have formed at the interfaces of air bubbles and milk.The phenomenon has been shown to be of importance in handling dilutions of milk in the course of bacterial enumeration.

Description: 1. An examination is made of some aspects of the replacement or exchange of bases by ammonium chloride solution, in a soil about which considerable information had been acquired regarding its physical, chemical, and mineralogical constitution, namely, the soil of Craibstone Experiment Farm, Aberdeen. Certain data in this connection are given.2. The “course of replacement” of calcium by ammonia, by successive applications of equal amounts of a normal solution of ammonium chloride is examined, according to the method of Gedroiz. Comparison is made between the results got for the Craibstone soil and those for a tshernoziem soil examined by Gedroiz. By means of graphs the agreement between the two soils as to the “course of replacement” is shown, and a distinction made between easily extractable calcium, and that more slowly removed in solution. The “course of replacement” of potassium and magnesium in the Craibstone soil is also examined.3. The presence of silicon, aluminium, iron and manganese is also noted in the extracts.4. The soil is also examined for “Total Exchangeable Bases” by extraction with normal ammonium chloride, according to the method of Hissink, with minor modifications.5. Exchangeable aluminium, iron, calcium, magnesium, manganese, potassium and sodium were found and in addition silicon was present in the extracts.6. The question of the presence of silicon, aluminium, iron and manganese in measurable amounts in extracts from acid soils is discussed.7. The relative proportions of exchangeable divalent and monovalent bases found were as follows. Calcium 85·02 per cent., magnesium 8·11 per cent., potassium 2·18 per cent., sodium 4·68 per cent. These results are in general agreement with those found for acid soils.

Description: An account has been given of the different methods adopted for extracting protein material from the juice of the mangold root and subsequent purification of the crude material.Three samples of protein have been isolated in different ways and their distribution of nitrogen determined by the van Slyke method.Two globulins and an albumin have been extracted from mangold seed, the two globulins being isolated very pure and an elementary analysis done. These two proteins differed in sulphur and nitrogen contents and different physical properties justified their being looked on as two distinct proteins.Distributions of nitrogen by the van Slyke method revealed differences in the globulins, especially in their contents of arginine and histidine.The similarity between the root and the seed proteins has been pointed out, and the root protein has been compared with animal proteins.

Description: (1) The herbage of the hill pastures in Great Britain is, in general, markedly poorer than that of the cultivated pastures in respect to silica-free ash, and each of the individual ash constituents, with the exception of sodium. It is also poorer, but to a less extent, in nitrogen.(2) The percentage of silica-free ash in the “not eaten” grass from the hill pastures is only approximately 50 percent of that in the “eaten” grass. This deficiency is fairly uniformly distributed over the ash constituents with the possible exception of sodium.(3) Despite these marked differences in the mineral content of the different types of pasture, there is very little difference in their caloric value as calculated by the method indicated.(4) Wherever sheep have a free choice in grazing they appear to eat, by preference, that herbage which contains the higher percentage of mineral ingredients.

Description: In human society, density of population is marked by striking variations. With these are associated geographic, social, and economic differences. Among the plant populations of our fields occur gradations of spacing or density which, by broad analogy, suggest problems akin to those arising from density differences in human populations. It is necessary to do no more than walk the length of one of the drill rows in a field of young corn to appreciate the general situation. The facts are patent some five weeks after sowing when the emergence of the seedlings is almost completed. Side by side with a foot length of drill in which are thirty plants may be another foot with only three. Complete gaps of 2 feet or more are to be found in places: in others the plants are almost too numerous to count. In every field of corn, even at this early stage, the density or closeness of the plants in the drills is extremely irregular. As the season advances various influences induce irregular reductions in the number of plants. Vermin and disease take sporadic toll. Competition between plant and plant with death or effective disablement of the weaker has some effect. Its intensity at any point is mainly determined by the density or closeness of the plants. By May, for winter corn, a static condition has generally been reached. Plants living then are likely to contribute grain and straw to the harvest. Among these survivors are great differences in spacing. This may be readily appreciated by uplifting and counting the roots in sample 1-foot lengths of drill on a stubble field.

Description: 1. Sampling of single roots of swedes by means of cores is subject to errors of various kinds, of which one, due to the asymmetrical growth of the root in a north-south direction, has previously been overlooked. Cores should be taken horizontally in a north-south direction.2. In the case of plants left standing in the field there is a marked decrease in dry matter content during winter and spring; this is presumably due to movement of food-material from the root into the developing flowering shoot. A detailed study of the metabolism of the swede during the winter is urgently needed, if only for the practical purpose of determining the “metabolic turning-point,” which is the ideal time at which to determine potential dry matter content.3. The fresh weight of a core is a function of the weight of the whole root (except in Tankard swedes).4. There is a well-marked negative correlation (autumn – ·66, spring – ·51) between dry matter content and fresh weight of core, and hence between dry matter content and size of root.5. For one pair of strains of common parentage clear evidence of the inheritance of dry matter content has been obtained. In other instances the figures are inconclusive.

Description: 1. Evidence is produced to show that the free water in a soil is 21.2. Wilsdon's modification of the Briggs-Shantz equation is discussed, viz., M = xH + 21, in which x = the vesicular coefficient. From this equation the vesicular coefficient of any soil can be found from the values of M and H.3. The values thus obtained agree for clay soils with those found by Hardy's method from the moisture at the point of maximum plasticity.4. The vesicular coefficient of a soil is greater than that of its subsoil.5. The total bound water = (M – 21), and the vesicular water = M – (21 + H). The vesicular water expressed as a percentage of the plastic soil is equal to the cubical shrinkage coefficient.

Description: In the summer of 1923, the Agricultural Education Association appointed a sub-committee to report on the present position with regard to the mechanical analysis of soils. This committee has now reported to the Association, which has adopted its recommendation that the former Agricultural Education Association method(1) of sedimentation in a beaker shall be replaced by one depending on the depth concentration relationship in a settling suspension. The reasons for this recommendation and the experimental work on which it was based will be of interest and use to soil workers generally. The salient features of the report have therefore been presented in the present paper, and an appendix of methods has been added. The full details of the official method will be published in Agricultural Progress, the journal of the Agricultural Education Association.

Description: The facts and considerations set out above provide the information necessary to enable an intelligent pig-keeper to compute on a logical and scientific basis a series of rations which from the energy point of view will produce any desired rate of live weight increase within the capacity of his animals. It is however necessary to make the reservation that the data apply strictly only to pigs of the Large White breed kept under good conditions and liberally fed.It should also be noted that the method can only be applied to animals of known age and weight.The method is applied as follows:1. From the age of the animals read off from the basal metabolism chart, Fig. 1, the intensity of the basal metabolism per square metre per hour.2. From the live weight—surface chart, Fig. 2—read off the surface area in square metres corresponding to the animal's live weight.3. Multiply the basal metabolism per square metre per hour by the area of the animal's surface in square metres. The product multiplied by 24 gives the basal metabolism of the animal per day.4. To get the practical maintenance requirement add to the basal metabolism per day 1000 calories to allow for an average amount of muscular effort.5. Decide the growth rate in pounds of live weight increase per day at which it is desired to aim. The growth rate curve, Fig. 4, will help in assessing this figure.6. Read off from Fig. 3 the calorie value per lb. of live weight increase corresponding to the live weight of the animals under consideration, and multiply the figure there found by the desired live weight increase in lb. per day. This will give the productive ration in calories per day.7. The total ration is then found by adding together the maintenance requirement estimated in 4 above and the productive ration estimated in 6 above. This gives the total ration in calories of net energy.8. Transform calories of net energy into lb. of meal on the assumption that 1 lb. of meal supplies to the pig 1000 calories, or preferably that 1 lb. of starch equivalent supplies 1500 calories.

Description: 1. The adaptation of plants to resist frost appears to depend on seasonal changes which give the protoplasm stability. A study has been made of the changes occurring in winter wheat plants, of varieties differing widely in winter hardiness, during the fall and winter months.2. By analysing the press-juice as well as the entire tissues at progressive dates, it has been possible to study the distribution of the more important constituents between the physiologically active cell fluids and the relatively inert supporting framework.3. One of the most important changes in the quantitative relations of the various plant constituents is the reduction in moisture content. This takes place to a greater degree in hardy varieties. The resulting concentration of colloids and sugars in the cell fluids increases the resistance to freezing.

Description: In attempting to interpret the results of two series of sheep feeding experiments, we have been confronted with the fact that the sum of the accepted figure for maintenance requirement and the allowance for the live weight increase produced does not account for the whole of the ration consumed. Sheep averaging 100 lb. live weight folded on swedes in the winter usually eat per week at least 100 lb. of swedes, 7 lb. of hay and 3½ lb. of cake and corn. Such a ration supplies per week about 11½ lb. of starch equivalent.Sheep fed in this way normally put on per week about 2 lb. of live weight increase, starting from store condition. It is true that figures for the composition of the live weight increase put on by store sheep are somewhat scanty, being practically confined to a series of analyses by Kern and Wattenberg (Journ. Landw. 1880) which give the composition of the live weight increase of store sheep as 44 per cent, water, 45 per cent. fat and 11 per cent, protein, which corresponds to 2200 calories or 2 lb. of starch equivalent per lb.The requirement for producing 2 lb. of such increase would therefore be 4 lb. of starch equivalent per week.Measurements of the maintenance requirement of sheep are likewise scanty. There are no recent measurements, but Armsby has recalculated the experiments of Henneberg, Kellner, Hagemann and Wolff, the most recent of which were made in 1893. These workers used two methods. The more scientific method of estimating by respiration experiments the storage of fat on a known ration and arriving at the maintenance requirement by deduction was used by Henneberg, Kellner and Hagemann. Recalculating and averaging their results, which differ widely, Armsby arrives at an average figure of 719 calories per day of net energy for the maintenance requirement of the 100 lb. sheep.

Description: The method used in this paper to reduce sunshine data is that developed by Fisher(1). It consists, briefly, in fitting to the distribution for each year, a curvewhere T0, T1T2, etc., are orthogonal polynomial functions of zero, first, second, etc., order in time. The constants s0, s1, s2, … etc., are found by least squares, and are correlated with similar rainfall constants (r0, r1, r2 etc.) and with the crop.The regression of the wheat yield on rainfall has already been found (1), so a method has been devised, whereby those results can be used in order to find the partial regression of wheat yield on the sunshine sequence, eliminating all rainfall effect.

Description: The laboratory study of the physical properties of soil and clays can conveniently be divided into three stages:(a) Moisture content comparable to that under field conditions.(b) Thick pastes.(c) Weak suspensions.The use of the plastometer for experimental work on intermediate stage is described and recent developments of the theory of the flow for thick pastes under stress are outlined. It is shown that certain constants defining the material can be obtained from the experimental data. The two to which special attention is given are the pseudo-viscosity (a quantity analogous to the viscosity of true fluids) and the static rigidity (which represents the energy required just to cause the paste to flow and a measure of the solid cohesive properties of the system). The latter quantity is related to other physical measurements made under very different experimental conditions, e.g. the resistance of the soil to the passage of cultivation implements; the effect of chalk, etc., on the soil resistance; the moisture content at which a well-kneaded mass of soil is about to become sticky.

Description: Methods for extraction, concentration and determination of minute quantities of soluble carbohydrates, lactic acid and volatile fatty acids have been described. Different factors affecting the accuracy of the determinations have been studied and corrections, where necessary, have been suggested.

Description: An account is given of observations made during the first two years' treatment of grass according to the “New System of Grassland Management,” i.e. periodic dressings of nitrogenous manure followed by rotational grazing.The grazing provided by the nitrogen and no-nitrogen plots in the two years is given, measured in cow-day equivalents.A method of sampling the plots with a view to determining the total weight of herbage produced and its chemical and botanical composition is described.Botanical and chemical results obtained by this method are given and discussed.The percentage of clover on the nitrogen plots is about one-quarter of that on the control plots.The dry matter of the herbage on the nitrogen plots has, on the average, contained 17·7 per cent, crude protein: that on the no-nitrogen plots 15·5 per cent. The average age of the grass when sampled was 35 days.

Description: This paper is a record of the composition of the milk of an abnormal cow, during a period extending over three lactations. Although this cow was found eventually to be suffering from tuberculosis of the udder and lungs, no signs of the disease were apparent during the first two lactations recorded.The milk produced by this cow was abnormal during the whole period under review. Fat percentages were very variable, but the solids not fat content was consistently low, only 2 per cent. of the total number of samples analysed exceeding 8·5 per cent. in this constituent. Protein and lactose percentages were much below the averages for normal milk, but in the case of total ash the mean figures were normal. Of the ash constituents, the soluble portion was very high and the insoluble portion correspondingly low, the former presumably indicating a high chloride content. The percentages of phosphoric acid and lime were considerably below the mean figures for normal milk.Lactose and soluble ash percentages show a marked negative correlation, and moreover support the contention of Porcher and others that a definite lactose-chlorine ratio exists in milk.It is suggested that an abnormally low solids not fat content (i.e. low protein and lactose) and abnormal percentages of the individual ash constituents may be a sign of incipient disease affecting the organs involved in the secretion of milk.

Description: (1) The solubility of the potash in 34 soil samples from 13 soils typical of large areas in the East of Scotland has been determined by the methods of chemical analysis using (a) hot concentrated hydrochloric acid, and (b) 1 per cent, citric acid solution, and the values obtained compared with the quantities of potash existing in the exchangeable form. The total mineral potash has been determined for six samples and Neubauer's method of analysis has been applied to 10 samples and again compared with the exchangeable potash.(2) The average value of the total mineral potash in the soils examined was 2·04 per cent., which indicates the presence of comparatively large reserves of potash in these soils. No relation was found to exist between the total potash, and the quantities soluble in hot concentrated hydrochloric acid.(3) The average value of the HCl-soluble potash was 0·50 per cent, and in the profile samples there was generally an increase in solubility with increase in depth of soil.

Description: This series of investigations embraces studies of the more important factors, external and internal, which govern yield in field crops of cereals. It has so far dealt with the causes and influence on yield of fluctuations in density of plant population and also with certain inter-field differences of environment. Throughout, an analytical method has been employed, in which periodic observations have been made upon small samples distributed over a representative acre in a field crop. The best size of sample has proved to be a one-foot length of row, i.e. row of plants as seeded by the drill. The basis of this method—a “census” of an acre of corn—has been described and critically examined in an earlier paper (Engledow(1)). Analyses of certain external factors affecting yield have been recorded by Engledow(2) and by Doughty and Engledow(3).

Description: Milk which has been heated to temperatures varying from 105–209° F. for half an hour differs from raw milk in its reaction to rennet in all cases.There is no change in the diffusibility of the nitrogenous substances in milk after heating to temperatures varying from 105–209° F. for half an hour.Heating to 175° F. and above for half an hour appears to reduce the diffusibility of the phosphorus content of milk.Heating to 125° F. and above for half an hour causes marked diminution in the diffusibility of the calcium content of milk.

Description: The object of this series of investigations is to secure detailed information concerning the composition, digestibility and nutritive value of pasture grass in its different stages of growth. The results which were obtained in these respects by cutting the herbage of the experimental pasture plot at weekly and at fortnightly intervals have been described in previous communications. During the season of the present experiment, the trials have been carried a stage further by the adoption of a system of cutting at 3-weekly intervals. The main findings of the 1928 investigation are recorded below:(1) Chemical composition of 3-weekly pasture cuts: The adoption of a more lenient system of cutting at 3-weekly intervals led to a slight lowering of the percentage of crude protein in the grass and a slight raising of the percentages of crude fibre and N-free extractives. On the other hand, no corresponding effect was noted in respect of the ether extract, SiO2-free ash, lime and phosphate, the percentages of these constituents being very similar in the weekly and 3-weekly pasture samples obtained in 1928. The falling off of the percentage of crude protein in the 1928 3-weekly-mown herbage, as compared with the weekly and fortnightly-mown herbage of 1925 and 1927 respectively, was not wholly the consequence of the more lenient system of cutting, but was also due in part to the protein-depressing influence of the droughty periods which were experienced in the 1928 season.

Description: 1. There exist in Trinidad large areas of deteriorated soils which have been under cultivation with a single short-term crop for generations. It has previously been established that these soils differ but little from those which still retain their fertility in their content of organic matter. By comparison with the latter, however, they are markedly acidic and so deficient in exchangeable calcium that a material improvement in their lime status appears to be a necessary preliminary to their amelioration. An examination has therefore been made of the means by which this may most successfully be accomplished.2. Determinations of the contents of exchangeable calcium and the pH values of a series of liming experimental plots indicate that:(a) Contrary to experience in England, finely ground limestone has proved a more efficient soil ameliorant than slaked lime.(b) Single relatively large applications of lime fertilisers have given more immediate beneficial results than small annual dressings.(c) The effect of liming appears to have been almost entirely restricted to the depth to which the soil is worked. This is doubtless due to the impermeability and lack of aeration which characterises heavy deteriorated soils.3. A significant increase in crop yield was obtained only on those plots which were later shown to have been rendered neutral in reaction by liming, and on which the degree of saturation of the top 6 in. of soil has been raised to 80 per cent. This value is comparable with that of the fertile soils of Trinidad.4. The experience of liming methods gained in Trinidad may be applicable to other areas of alluvial soils under cultivation in the tropics.

Description: 1. Material is presented which shows month by month the lactation yields of cows in respect of milk and fat. Morning and evening yields are treated separately and differences in relative proportions found.2. Smaller proportions of milk and of fat at the morning milkings are yielded in early lactation by all cows, but this point is most pronounced in heifers and also in heavy yielding cows with relatively small udders. It is suggested that with such animals reabsorption of milk occurs during a long night interval.3. Seasonal variations in yield of milk and fat are shown. It is found that the morning milking does not respond as much as the evening milking to the stimulus to secretion which functions during May and June.4. The quality of milk at different seasons of the year is discussed.

Description: 1. A method for the rapid determination of lime requirements in laboratories equipped with the quinhydrone electrode is described. (10 gm. of soil are mixed in a small wide-mouthed bottle with 40 c.c. of neutral 0·2 M CaCl2 solution. The mixture is then titrated with 0·03 N lime-water in successive portions of 5 c.c, with three minutes' shaking between each addition. The pH value of the mixture is determined after each addition, and the titration continued until the reaction has passed pH 7·0. The results are plotted, and the exact volume of limewater needed to give a final reaction of pH 7·0 is estimated from the graph.)2. The method is compared with the Hutchinson-MacLennan method for a series of soils of different textures and different initial exchange reactions. It appears to yield more reliable results; it is less tedious; it is very rapid, and results obtained thereby can readily be reproduced.

Description: (1) It is proposed to estimate the amount of organic carbon in soils by determining the amount of sulphur dioxide produced in the ordinary Kjeldahl digestion. The gaseous products of reaction are passed through standard iodine solution, and the excess iodine titrated with standard sodium thiosulphate. Details of the method are given.(2) The results obtained with a number of soils of differing character and origin are compared with the figures obtained for organic carbon by dry combustion. The sulphur dioxide method gives results which average 89.6 ±1.03 per cent, of the combustion figures. It is proposed therefore that the percentage of organic carbon found by this method should be corrected by the factor 100/89.6 = 1.116.(3) The percentage recovery of carbon indicated by the proposed method is rather higher for pure substances but still falls short of 100 per cent.(4) The proposed method is applicable to carbonate soils without the necessity for any correction for inorganic carbon.(5) It is likely that soils containing inorganic reducing substances such, as sulphides will give high results by the proposed method.(6) Absorbing the sulphur dioxide in 25 per cent, sodium bichromate, it is possible to determine the carbon dioxide by passing the gases through standard baryta in a Reiset tower. The organic carbon thus indicated agrees with that by the sulphur dioxide method.(7) From data with certain peats, it appears that the factor 1.724 for converting organic carbon to organic matter is too low.

Description: Inconsistency in the returns of sugar percentages from the factories has often perplexed growers and has at times given rise to some mistrust of the analytical procedure. Consignments of beet lifted on the same day and from the same field have been credited by the factory with widely different sugar contents. This has occurred within the writer's experience, even though the precaution was taken of loading the cart loads of beet into two trucks alternately, thereby eliminating any possibility of one truck being filled with beet from a better part of the field than the other.

Description: 1. Both Pseudoperonospora Humuli and Phytophihora infestans are extremely susceptible in the zoospore stage to the action of weak solutions of soap or saponin. The zoospores are caused to disintegrate suddenly, apparently by changes in surface tension, within 60 seconds, in solutions containing over 0·1 per cent, soft soap. Those of P. Humuli are more vulnerable than those of P. infestans.2. The fungicidal action of soap and saponin mixed with certain adherent substances was tested on hop plants.3. The power of adhesion and the fungicidal efficiency of the mixtures were tested by allowing single drops to dry on the surface of watch glasses and by then adding drops of water containing zoospores.4. Other substances, e.g. aluminium-lime mixture, glycerine, iodine, bromine, were also found to kill zoospores rapidly.

Description: Organic materials with a C: N ratio ranging from about 85: 1 to about 10: 1 were submitted to nitrification tests in an acid and in an alkaline soil during a period of 6 months. In the acid soil only pea pod meal, with a C: N ratio of 13·3: 1 showed an increase in inorganic N over control; in the alkaline soil the limit above which no nitrification will occur within a period of 6 months was at C: N = 26: 1; below this limit the rate of nitrification increased rapidly with decreasing C: N ratio. Unnitrified N was left behind in a quantity corresponding to 1·5–2·2 per cent, of the original material, the percentage being higher in the case of materials rich in N.All the materials tended to increase the content of “a-humus” in the soil, though not to the same extent or in the same manner. More “a-humus” was produced in the alkaline than in the acid soil, except in the case of farmyard manure. Straw, sweet clover, lupin and farmyard manure apparently acted both through their lignin content and through the synthesising action of microorganisms, since they increased the amounts of both N and methoxyl in humus. Mycelium of Polyporus contains a fraction possessing the properties of “humic acid,” rich in N, but devoid of methoxyl, which persists in the soil.

Description: The metabolism of a Berkshire and a Middle White pig has been investigated by means of the calorimeters at the School of Agriculture, Cambridge. The general routine and technique of the observations have been as heretofore.Measurements of the fasting katabolism of each of the two pigs have been obtained in a series extending from an early age to maturity, and the phenomena in general follow the lines of those originally discovered in the Large White; but the fasting katabolism of the Middle White was below that of the Large White earlier studied.The fall in body temperature and in metabolism during the fasts were found to be correlated, and the possible effect of skin colour in this matter is noted.The effect of environmental temperature is investigated and reasons are given for supposing that the critical temperature of the Middle White pig is very low.It is concluded that the existence of a maximum somewhere in the curve showing fasting katabolism per unit area at different ages is necessitated by the two physiological facts (a) that warm blooded animals have to be maintained at a temperature which varies only within very narrow limits, and (b) that the processes of growth are accompanied by waste of energy as heat.

Description: 1. The sugar-cane in Trinidad is subject to blight, caused primarily by the sucking action on its leaves of a Cercopid, Monecphora (Tomaspis) saccharina Dist., commonly known as the “froghopper.” The intensity of the injury sustained by the cane appears to depend largely on the condition of the soil in which it is grown. An investigation has, therefore, been made of the extent to which certain soil factors are associated with the reaction of the cane to froghopper attack.2. The data obtained show that the mechanical composition of the soil and its content of organic matter bear little relationship to the damage caused. The blighted soils differ from those blight-free, however, in that, whereas the former are devoid of calcium carbonate and, as a rule, markedly acid, the latter almost mvariably contain at least traces of this substance, and in general are alkaline or slightly acid only. These differences suggest that the lime status of the soil is a factor of primary importance.

Description: 1. The paper discusses experiments laid down at 39 centres in Great Britain to test the value of seed inoculation for lucerne.2. The seed was inoculated by treating it with a suspension of the nodule bacteria in skim milk containing 0·1 per cent, calcium di-acid phosphate, the method developed by Thornton and Gangulee.3. In the west and north of England the treatment greatly benefited the lucerne and often enabled a crop to be obtained where the untreated lucerne failed. At 12 centres in this area at which the crop was weighed, inoculation increased the yield by over 20 per cent, in all cases save one, where spread of the bacteria vitiated the result.4. The improvement sometimes showed itself as an increased yield and sometimes as an increase in the nitrogen content of the hay. In most cases both these effects were produced.5. In the midland and south central counties inoculation usually produced a temporary improvement, the untreated plant eventually catching up with the inoculated. The effect of inoculation is very much greater where the young lucerne has to compete with a cover crop. Weight results from 8 centres in this area showed increases from inoculation of over 20 per cent, in 4 cases, smaller but significant improve-ment in yield or nitrogen contentin 3 cases, and no significant effect in one case.6. In East Anglia and Kent untreated lucerne usually develops plenty of nodules. An exceptional condition occurred in a trial at Tunstall Heath, Suffolk, on sour light land, where liming and inoculation produced a fair plant although the uninoculated lucerne developed no nodules and failed.7. There is evidence that, when the seed is inoculated, the chances of success with lucerne are on the whole as good in the west and north of England as they are in the south-east.8. In a number of trials sown in 1926 better results were obtained by sowing the seed in a light cover crop in spring than by sowing in June or July.

Description: 1. An account is given of the geology and mineralogy of the soils of a small area characterised by diverse rock groups, which are mainly covered by glacial drift. The topography is also varied. The soils are mainly derived from boulder clay, glacial sands and gravels, and alluvium, the remaining soils being formed on screes and hill-wash. The underlying rocks are lavas of Old Red Sandstone age and sandstones and shales of Carboniferous age.2. A similarity in mineral content of the soils on glacial material and alluvium is shown. All these soils have a high content of fresh ferro-silicates. The soils on the screes and hill-wash are characterised by their content of rock fragments and iron oxides, but minerals from glacial material are also present, though to a minor extent.3. The soils on the drift material contain potash, phosphate and lime-bearing minerals.4. The varied nature of the parent materials has given rise to varied textures in the soils. The soils on the boulder clay are the heaviest, while, the soils on the fluvio-glacial material are very variable.5. The mineral content of the matrix of the boulder clay is similar to that of the local rocks, only the rarer minerals being derived from external sources.

Description: The problem of the use of water by cultivated plants during the period of their growth is of great scientific interest. It is certainly of prime interest for the farmers of a dry region where to secure a yield everything depends in most cases upon the problem of moisture.When studying the problem of the use of water by cultivated plants under field conditions the importance of extremely unstable and widely varying meteorological factors is evident. The fluctuations are especially large and irregular with respect to moisture.

Description: (1) There is a definite seasonal variation in the mineral content of the pastures examined between the months of May and October, which is most clearly shown by the CaO, which rises to a maximum and then steadily falls; and to a less extent by the silica-free ash, P2O5and Na2O.(2) The chlorine content did not show a corresponding variation; its tendency being to maintain its high percentage through the later part of the season.(3) The nitrogen, on the whole, showed a variation corresponding with the calcium, though the range was markedly less.

Description: (1) Bent-leg appears to be due to a mineral deficiency and can be prevented by a mineral supplement.(2) Bent-leg appears, by the growth curves, to be correlated with a general lower nutrition.(3) The occurrence of bent-leg on pasture grass would indicate theoretically that an extreme lack of some mineral constituent has become evident in the grass itself.(4) Pasture analyses show that these grave mineral deficiencies do actually occur in large pastoral areas, and that these areas are correlated with high stock death-rates.(5) The mineral elements of the ration are therefore no less important to the pastoral farmer than to any other stock feeder.

Description: Two fundamental explanations have been advanced to account for the unequal distribution of electrolytes on either side of a cell membrane: the one bases the unequal distribution on the existence of a cell membrane of so-called selective permeability, by which the membrane is endowed with the property of presenting varying resistance to the passage of different ions; the other regards the unequal distribution as being due to the selective action of the cell constituents themselves. This latter theory regards the cell primarily as a system in which the distribution of electrolytes is governed by the equilibrium existing on either side of a membrane permeable to electrolytes but impermeable to other ionised constituents of the cell.

Description: An investigation has been described in which an attempt has been made to measure the losses of dry matter in a number of regularly spaced layers of silage contained in a tower silo, the immediate object being to determine the average loss of nutrient matter in the entire mass of material. The work was continued over the period of two silage seasons. The more important findings are summarised below:1. It is usually asserted by writers on ensilage that the attainment of such high temperatures as are necessary for the production of “sweet” silage necessarily involves an excessive loss of the dry matter of the crop as a consequence of the oxidation of carbohydrate. This statement has been shown to be erroneous both on theoretical grounds and on the grounds of actual measurements of the losses of dry matter entailed in the production of “sweet” silage. The amount of destruction of carbohydrate bears no significant relation to the temperature attained during preservation, and the factors of (a) juice drainage, (b) bacterial decomposition of carbohydrate, (c) partial spoiling by undesirable bacterial activity, as with “sour” silage, are of much greater significance in causing unduly large losses of carbohydrate.2. The results obtained in this investigation with crops containing from 26·5 to 33·9 per cent. of dry matter show that “acid brown” silage can be made in the tower silo with an average loss of dry matter equal to 5–6 per cent. of that contained in the green crop. It is further concluded that “sweet” silage, if made under good conditions, can also be produced in the tower silo with an average dry matter loss of the same order. With “green fruity” silage, the average loss under proper conditions of ensilage in tower silos is of the order of 8–9 per cent. The evidence affords strong disproof of the statement that the ensilage of green crops cannot be accomplished without large losses of nutrient matter.

Description: Six heifers have been measured every week, for 5 weeks before calving and 6 weeks after calving, with the object of ascertaining what errors would be introduced by taking one set of measurements during such a period, as representing the size of the heifer at parturition.The gross standard error was found to be 0·834 cm. in measuring shoulder height and back length and 0·605 cm. in measuring height to the elbow.During the period these heifers were growing as follows: shoulder height, 0·159 cm. per week; back length, 0·124 cm. per week; and elbow height, 0·079 cm. per week.When allowance was made for growth the net personal errors of measurement gave standard errors of 0·636 cm., 0·727 cm., 0·547 cm. respectively for shoulder height, back length and elbow height, and the errors were, apparently, distributed normally.

Description: (1) A review of the literature on the digestibility of wheat by poultry revealed the fact that, whereas there appeared to be but little variation in the digestibility coefficients for organic matter and N-free extract, considerable variation existed in the digestibility coefficients for crude protein, fibre and ether extract. It was considered desirable, therefore, to carry out digestibility determinations of known varieties of English wheats in order to ascertain how far such variations could be attributed to different varieties of wheat having been used in these experiments.(2) Experiments carried out with Little Joss wheat and Yeoman II wheat gave closely concordant results for all nutrients other than ether extract.(3) The results obtained in these experiments support the view that the digestibility of crude fibre by poultry is negligible.(4) Except in the case of crude fibre and ether extract, poultry appear to be able to digest wheat as efficiently as other farm animals. Poultry are, however, distinctly inferior to other farm animals in their capacity to digest crude fibre and ether extract.(5) The results of the present experiment show general agreement with previous work, except in the case of protein, where the digestibility coefficients are distinctly higher than those hitherto recorded. The explanation of this result may possibly be sought for in the improved methods used in the estimation of uric acid and ammonia

Description: The addition of sodium silicate has been found to increase the yield of barley to a considerable extent, this effect being most marked when no superphosphate is added.The phosphatic content of the ash is not greatly increased in the grain, and is diminished in one case in the straw; the conclusion from this observation that the silicate does not act by releasing soil phosphates, but as a plant stimulus, overlooks the fact that the addition of silica to the ash naturally reduces the percentage of other constituents, and should be discounted.The phosphate removed annually in the crop is greatly increased on the plots receiving silicate, even when this removal has continued for many years without replacement.That additional phosphate is actually made available to the crop on the plots receiving silicate is shown by the increase in the proportion of phosphate in the dry weight of the crop, which appears on all the plots, and at all periods.This increase is quantitatively sufficient to account for the increased yield in grain and straw, without postulating the aid of any stimulus to plant growth.

Description: 1. The form of the dispersion curve obtained by single dispersion treatment below μ/x varies greatly with different soils and with the same soil saturated with different bases. There is no connection between the proportion of very fine material (e.g. below 0·5μ) and other important soil properties. The proportion of the very fine material determined in this way would not, therefore, afford any indication of the “colloid” properties of the soil. If the proportion of fine material were estimated by a decantation method the results might be substantially modified.2. Under the same conditions of dispersion sodium soil is better dispersed than ammonium. Sodium carbonate should therefore be the best medium for mechanical analysis.3. No case has been met with where the proportion of clay found is affected to an important degree by the use of hydrogen peroxide.4. With no soil tried was the number of decantations reduced by the use of acid pre-treatment; those examined gave the same clay content i f sufficient puddlings with sodium carbonate were used with or without acid.5. No method has been found whereby certain soils can be dispersed i n a single operation as is required in the pipette method. In some cases this is due to gypsum, but there are others in which the cause of the difficulty of dispersion is not yet known.6. In the cases examined sodium carbonate gives a higher result than ammonia when using the International pipette method.7. For Sudan soils decantation methods appear essential, hydrogen peroxide unnecessary, acid pre-treatment not essential, and sodium carbonate better than ammonia. We are of opinion that the same holds good for many other soils.

Description: The following solutions were tested with respect to their fungicidal properties towards the “powdery,” conidial stage of Sphaerotheca Humuli on young hop-leaves in the greenhouse.(1) A solution of potassium polysulphide containing 0·092 per cent. polysulphide sulphur proved fungicidal, whilst one containing 0·066 per cent. was not quite fungicidal.(2) A solution of sodium polysulphide containing 0·12 per cent. polysulphide sulphur proved fungicidal. It seems probable that solutions of sodium and potassium polysulphides possess the same fungicidal values.(3) Lead arsenate proved to be considerably less fungicidal in action than lead thioarsenate, dicalcium arsenate or disodium arsenate. A solution of lead arsenate containing 0·1 per cent. As2O5 proved to be not quite fungicidal, while one containing 0·204 per cent. As2O5 proved fungicidal.(5) Solutions of calcium polysulphide and of lead arsenate at concentrations below fungicidal strength when mixed together proved to be fungicidal.

Description: The exploitation of the herbage by means of the herbivora is a most ancient process. It seems at first sight that special nutritional problems are not involved, since flocks and herds are kept under conditions approximating very closely to the original environment of their species. In comparatively recent years, however, masses of herbivora have been in some cases either confined so that their range is greatly limited from that of their widely-grazing forbears, or transferred bodily to grasslands previously uninhabited by them, or transformed by the skill of breeders into creatures with a much higher output, and in consequence, a much higher intake. These novel factors have produced problems of their own which are not yet solved, though they have been, with some success, tackled by the practical man largely by empirical methods.

Description: (1) Exchangeable magnesium and potassium can be determined in carbonate-free soils by the use of 0.5 N acetic acid as a leaching agent.(2) A method is described for the determination of the total exchangeable bases present as acetates in the leachings.(3) The results obtained by this method differ from those obtained by summation of separate determinations by an amount equivalent to the sulphates and chlorides present.(4) It is suggested that the total exchangeable bases by the proposed method gives a truer measure of the exchangeable bases than methods in which bases present as sulphates and chlorides are also reckoned in.

Description: 1. The day to day variability in the yield of milk and fat of cows is affected by many factors, two of which are stage of lactation and season of the year. Variability is high during the first month of lactation (particularly during the first few days after the calf is weaned), but after this a fairly constant variability may be expected. Under the conditions of management in the herd under discussion and probably in most herds in Southern England variability is highest during the month of May and also tends to be higher during the summer than the winter months.2. A method is presented of calculating the variability in the yield of mixed milk from a herd of cows and the error to be expected when milk records and fat percentages of individual cows are calculated from a few samples.3. When cows are milked twice daily at unequal intervals the yield of milk obtained in 24 hours is slightly less variable if a morning milk yield is added to the subsequent evening yield, than if an evening yield is added to the subsequent morning yield.

Description: 1. The acid method previously described has been used to evaluate samples of pyrethrum derived from both Swiss and Japanese seed, with equally successful results.2. A rapid method for the evaluation of pyrethrum by a determination of pyrethrin I is described.

Description: (1) Animals on a calcium-deficient diet suffer periodically from loss of appetite though the ration is in every other respect satisfactory.(2) The results of twenty-two digestion trials show no enhanced effect on the digestibility of the organic constituents of the food on adding calcium carbonate to a lime-deficient ration.In conclusion, I wish to express my thanks to Prof. T. B. Wood, F.R.S., for giving me the necessary facilities to carry out the work; to Mr H. R. Davidson, M.A., for placing the experimental animals at my disposal and also to Dr H. E. Woodman for his active interest and supervision at all stages of the work.

Description: The scheme of soil classification which finds most favour among scientists to-day has come from Russia and is the work of a band of brilliant and enthusiastic investigators whose labours have brought some order to what was otherwise chaos. The object of this communication is to endeavour to show how it is possible to modify the views of this school so as to make them apply to British conditions, and how the majority of British soils may be brought within the envisaged scheme.

Description: (1) The physiological effects of calcium-deficiency on pregnant sows are briefly discussed. Results are given which demonstrate that a deficiency of lime in the food has no detrimental effect on the live weight of the young piglings at birth thus showing that up to parturition it is the mother organism that suffers and not the offspring.(2) Storage of nitrogen takes place throughout pregnancy but the results indicate a considerably enhanced conservation within three weeks of parturition. The average daily retention of nitrogen by the high-calcium group of sows was 12·51 gm. and by the calcium-deficient group 9·78 gm. The normal sows therefore stored 1439 gm. N and the calcium-deficient 1125 gm. N during the gestation period. It is shown that storage of protein during pregnancy is greatly in excess of the foetal requirement, so that the mother organism, during gestation, adds on a reserve supply of protein in preparation for parturition and lactation.(3) Ash ingredients were retained at all stages of gestation by both groups of sows. The addition of calcium carbonate to the food, however, resulted in an increased retention of ash. The percentage of the ash intake in the faeces was very similar in both groups, but the percentage of the intake in the urine was distinctly higher in the calcium-deficient sows indicating a more economical utilisation of ash by this group.

Description: (1) A solution of dicalcium hydrogen arsenate at a strength of 0·0125 per cent. As2O5 was fungicidal to the conidial stage of Sphaerotheca Humuli, while at 0·006 per cent. As2O5 it was not quite fungicidal.(2) Lime casein containing calcium hydroxide when added as a spreader to calcium arsenate was shown to reduce the fungicidal properties of the calcium arsenate spray.(3) A solution of calcium thioarsenate at a strength equivalent to 0·006 per cent. As2O5 was fungicidal to the above fungus, while at 0·003 per cent. As2O5 it was below fungicidal strength.(4) It is suggested that the increased fungicidal properties of the mixed lime sulphur-lead arsenate spray are due to the presence of calcium thioarsenates.

Description: The development is recorded of the series of experiments with potatoes at Rothamsted during 1925–27, designed to examine the quantitative response of yield to varying quantities of nitrogenous and potassic manures, and to test the relative value with this crop of different sources of potash.While rather precise comparisons were obtained on the qualitative question by means of Latin squares in 1925–26, the reality of the depression ascribable to chloride could not be demonstrated in these years, but became clearly apparent when in the following year, the qualitative experiment was merged with the quantitative one.In the earlier quantitative experiments, although satisfactory responses were obtained, the precision of the results left much to be desired, since only four replicates could be used. When by merging the experiments this was increased to nine replicates, much smaller responses were clearly measurable.The large and complex type of experiment finally adopted thus supplied more precise information on both heads than could previously be obtained, and in addition to a more thorough exploration of the different combinations possible.

Description: (1) A gasometric method for the determination of organic carbon in soils by the use of sulphuric-chromic acid mixtures at 100° C., as suggested by Watts in 1902, is described, and recommended for use in routine soil analysis.(2) The method is compared with the Kjeldahl procedure recently introduced by Robinson, McLean and Williams, and is found to give results which are generally similar, though numerically slightly lower.(3) The wet combustion method is somewhat simpler than the Kjeldahl method, but it has the disadvantage that nitrogen determinations cannot be made simultaneously, so that its usefulness in studies on soil organic matter is decidedly less.

Description: Experiments were carried out at two centres in Leicestershire during the spring of 1928, with the object of comparing the values of mangels and dried sugar beet pulp in the winter ration of dairy cows.Two groups of cows were selected at each centre, and the usual method of feeding for a period on one ration and then reversing, was adopted. Composite samples of the milk from each group of cows were taken at six consecutive milkings per week, during the period of the experiment. Determinations of fat and solids not fat were made, and the yield of milk at each milking recorded.Although there are indications that the change of ration caused a slight temporary variation in the quality of the milk, the secretion of milk solids followed, in a general way, the variation in yield: This is confirmed by the average composition figures representing the whole of the milk from each particular ration.Thanks are due to Mr Thos. Hacking for placing every facility for obtaining these data at the disposal of the author.

Description: The investigation bears out the conclusion of the Rothamsted experiments that leaching out may occur any time throughout the winter up to March, or rarely April.The loss of nitrates is directly limited by the amount of drainage and so is indirectly determined by the rainfall, and by temperature—as it affects the rate of evaporation.All three nitrogenous fertilisers are shown to lose well over 50 per cent, of a normal dressing by leaching out during the winter, but the loss is greatest in the case of sulphate of ammonia, least in the case of rape dust, calcium cyanamide being intermediate.The writers wish to express their indebtedness to Miss N. Sugg who carried out the experimental work in the first winter.

Description: In the past the standard method for determining the chloride content of soils has been to titrate with silver nitrate using potassium chromate as indicator. In most cases, the soil must be filtered through a filter candle and where in favourable cases filtration can be dispensed with, it is necessary to wait until the soil has settled before aliquot portions can be pipetted off and titrated.

Description: In a field trial with lucerne grown from seed treated with varying doses of culture it was found that the numbers of nodules were increased as the dose was raised from 2,500 to 20,000 organisms per seed (56 to 7 Ib. of seed per culture). Storing the seed for periods up to 28 days between inoculation and sowing, caused some loss in the nodule numbers. This loss was greatest between 1 and 7 days' storage.The difference in dose of culture and in period of storage did not significantly affect the crop subsequently obtained from the inoculated plots, whose yield was, however, much above the uninoculated.In a pot experiment made with runner beans, it was found that increase in the dose of culture above 1,280,000,000 organisms per pot containing six seeds was still capable of increasing nodule numbers but not to an extent proportional to the increase in dose.The experiment does not exclude the possibility that the restriction in effect of very heavy doses may be due to the soil population becoming saturated with the bacteria. On the other hand, observations on lucerne plants grown aseptically on agar and inoculated with a pure culture, showed that even when excessive numbers of the bacteria immediately surrounded the root hairs, only 4 per cent, of these were infected.

Description: 1. (a) Pyrethrin I and II have been isolated by the method of Staudinger and Ruzicka from the insecticidal plant Pyrethrum (Chrysanthemum cinerariaefolium). Both are shown to be highly toxic to the insect Aphis rumicis.(b) Pyrethrin I was found to be the most toxic substance so far tested by us and, as it was about ten times as toxic to these insects as pyrethrin II, it is concluded that it is mainly responsible for the contact insecticidal value of pyrethrum.2. Two micro-analytical methods of determining the pyrethrin content are described, (a) By means of the acids after hydrolysis, (b) By means of the semicarbazone. They are given on pp. 278, 282.3. The analytical results obtained for a series of pyrethrum samples agreed with their observed insecticidal properties to Aphis rumicis.4. Comparisons of the pyrethrin contents, as estimated, with the results of direct toxicity experiments both on the pyrethrum samples and the pure pyrethrins, confirm the validity of the analytical methods.5. There was a significant and positive correlation, in the samples tested, between the amounts of pyrethrin I and II.6. Insufficient data are available to show a significant correlation between the size of flower-heads and the content of poison, or to draw conclusions as to the effect of external conditions such as soil, weather or age of bed.

Description: A Unique correlation has recently been obtained from some experimental data at Rothamsted. In the autumn of 1924 a set of 47 unmanured plots were laid out in Sawyer's Field, and were sown with wheat to test the uniformity of the fertility of the soil. The plots were each ·098 acre. The produce of grain and straw from each was recorded, and an examination of the figures showed that the straw yield recorded for plot 1 A was much lower than one would have expected under normal circumstances. A careful enquiry into the matter revealed that by an oversight a weighing of straw had been removed from the scales before the weight had been entered in the record. As it was impossible to verify the exact value of the missing entry, the yields from this plot were omitted from all statistical reductions of the data, leaving 46 plots upon which to base an estimate of the various statistics.The soil was found to be very variable in fertility, the average yield of total grain per plot being 149·57 lb., with a standard error of 6·39 lb. and the average yield of total straw per plot was 194·35 lb., with a standard error of 7·55 lb.The grain and straw yields of the 46 plots are shown in the accompanying diagram. The very close association between the total weight of grain and total weight of straw is evident. The amount of the relationship was measured by correlating the 46 pairs of values.

Description: 1. The main results of soil investigations on the rôle of aluminium in soil infertility are reviewed, with particular regard to the physicochemical principles involved.2. Magistad's conclusion that soils or other nutrient media whose reaction values lie within the range pH 4·7 and pH 8·5 do not contain aluminium in soluble form, and are probably therefore not toxic to plants, is discussed in the light of modern knowledge of the properties of hydrous alumina and its peptisation phenomena.3. Dialysis experiments which have led to this generalisation are criticised on the grounds that they do not take into account the disturbing effect of dialysis on hydrous colloidal systems, and that dialyser membranes do not simulate plant-cell membranes.4. Aluminium may possibly penetrate plant-root cells, and, under certain conditions, may be translocated, within the plant body, in at least four different forms, namely, (a) simple ions, (b) more complex colloidal electrolytes, (c) co-ordinated complex anions, and (d) organo-compounds. These may conceivably be interconvertible.5. Aluminium appears to exert true toxic effect only when presented to plant roots as simple ions, or as the more soluble colloidal electrolytes. Apparently, the degree of toxicity varies for different plant species.6. The reaction conditions of nutrient media and of plant saps doubtless largely decide the form in which aluminium occurs therein. At reactions approaching the isoelectric point of hydrous alumina, toxic effects may never be exerted, although the assignation of a strict reaction-range applicable to all soils or nutrient media, and to all plant species, is probably inadmissible.7. Non-toxic forms of aluminium may apparently accumulate under certain conditions at definite tissue regions of certain plants, and may disturb their metabolic processes, disposing the plants to certain diseases.8. Within the reaction-range at which toxic aluminous solutes cannot exist in soils or other culture media, hydrogen-ions may exert controlling influence on plant growth, and may thus be of major significance in natural plant distribution, and in the behaviour of plants growing in normal agricultural soils.

Description: 1. The omission of the tension in the air-water interface has introduced an erroneous factor into Haines’ formulae; certain additional factors have also crept into his expressions for average stress.2. With these corrections, the stress due to moisture varies comparatively little with changing water content, though falling slightly throughout the range. The energy needed to cause rupture rises continuously in a manner not unlike Haines’ measurements, and should more probably be associated with them than should the tensile stress.3. The geometrical approximation used by Haines gives a close geometrical representation of the figure, but a mechanical approximation which is less satisfactory. Since neither the formulae connected with the true curve, nor the tables needed to use them, are readily, accessible, sufficiently exact numerical data have been here put on record.

Description: The occurrence of xanthin calculi in the kidneys of sheep on certain poor pastures on the Moutere Hills in the Nelson district is reported and described. The incidence of xanthin calculi is associated with poor stock results over large areas. Poor lambing returns, high mortality of stock in certain seasons, low milk yields and inability to fatten stock are common features of many farms on the Moutere Hills soil. On one small farm, grazing 120 sheep, no less than 12 sheep which have died or have been killed during the last six months have had calculi in the kidneys.The Moutere Hills soil type is shown to be highly deficient in both lime and phosphate. Great increase in crop production invariably accompanies the application of lime and phosphate to the land.

Description: In an attempt to determine the rôle of phosphates in tomato culture tomato plants have been analysed for potash, phosphoric acid and nitrogen.In unmanured plants the fruit is of inferior quality but the weight as picked is 2·6 times that of the foliage and stems of the same plants. In manured plants this ratio is 1·6. The relative efficiency of the plants under the two sets of conditions is discussed.Manured plants have a higher ash content than unmanured plants.

Description: 1. The variations in production due to age have been investigated with the records of 738 Ayrshire cows for 4380 lactations.2. Milk and butterfat production increase up to about 7 years of age and then show a decrease.3. The fat percentage for 3-year-olds is higher than that for older cows.4. After 3 years of age there is little change in the fat percentage with age that is of any practical significance until advanced ages are reached, when there may be a fall of importance.5. The increase in production associated with age is probably attributable, in part, to the growth of the secretory tissue of the udder and to body growth in general.6. Part of the increase may also be due to an improvement in functional activity through use.7. The tendency for milk to show a slightly lower fat percentage as the cow advances in age is probably due to the fact that as the milk yield changes the fat yield changes in the same direction but at a slower rate.8. There is little known regarding the influence of very advanced age on production, but it is probable that many cows maintain for a long time the production associated with maturity, and then decline slowly.9. Heifers with a low fat percentage need not as a rule be expected to test higher on reaching maturity.10. It is probable that the increase in production with maturity is associated more closely with high initial production than with persistency of production.11. Correction factors for age are presented.

Description: It is of great importance that milk should possess a pleasant flavour, but in spite of much trouble which is devoted by farmers and dairymen to this aspect of dairying, it happens from time to time that mishaps do occur. Taints and flavours in milk are due chiefly to the following three causes:1. The activity of contaminating micro-organisms.2. The action of milk on metals.3. The influence of the foods eaten on the milk produced.It must be admitted that we have very little knowledge of the subject of milk flavours and taints, and there seems little doubt but that the blame for many taints caused by micro-organisms has been associated wrongly with foods and sometimes with manures.

Description: Data from 26 flocks, involving a total of 5014 pure-bred Southdown ewes, were available for analysis and discussion. For ewes of all ages the proportion giving birth to twins is closely associated with the total yield of lambs, and while barrenness and abortion may to a certain extent be due to the same causes, it is those factors which cause abortion which also affect the yield by reducing the number of single births, rather than the number of multiple births.The low fertility of shearling ewes is due to barrenness through reduced or delayed ovulation.The writer wishes to express his thanks to the breeders who supplied the records of their flocks and particularly to the Honorary Secretary of the Southdown Sheep Society for his help in the collection of these records.