ALBERT

Description: The heavy yields of sugar beet tops which remain on the land after the removal of the sugar beet crop may be utilised in two ways. They may either be ploughed into the land as manure, or they may be fed to stock. Where large areas of sugar beet are grown, and where in consequence it may not be possible to secure consumption of the whole of the tops before decomposition of the material sets in, a combination of these two methods of utilisation may be resorted to. In other words, the feeding of the tops may be continued so long as they remain wholesome, after which the remainder may be ploughed into the land.In view of the present importance of the sugar beet crop in English agriculture, and the urgent necessity of making the fullest possible use of all the various by-products arising in connection with this crop both in the field and in the factory, it is of importance that data should be available relating to the value of sugar beet tops both as a feeding stuff and as a manure. The purpose of the present communication is to detail the results of investigations which have been carried out with a view to securing such information.

Description: The practice of applying nitrogenous fertilisers to cereal crops as a top dressing is one which has become firmly incorporated into normal farm routine.The classic wheat experiment on Broadbalk field shows that to apply all the nitrogenous fertiliser at the time of drilling the seed in autumn leads to a diminution in crop when compared with the yield of a plot in which only a quarter of the nitrogenous fertiliser was applied in autumn.

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 determination of dissolved oxygen by Thresh's method may lead to discordant results because of the loss of iodine, which is carried away by the gas passed through the apparatus during the titration.A modified method is described, which eliminates the above error and obviates the necessity for making separate determinations of the dissolved oxygen of the reagents used.Correction for the nitrites present in the water can be made by making separate determination by the Griess-Ilosway colorimetric method.

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. The various classes of insecticides are outlined, and the sense in which the term “contact insecticide” is used is denned as one which is brought into external contact with the insect, either as solid, liquid or vapour.2. An analysis is made of the relationships between chemical constitution and insecticidal action in the vapour phase. There is rough correlation between both the molecular weights and volatilities of organic compounds and toxicity, but it is probable that these relationships are only indirectly involved and that they indicate a connection of a more direct kind with some other property such as adsorption.3. An account is given of the toxicity to insects of certain plant products. The most potent of these are certain tropical leguminous plants used as fish-poisons. A brief account is given of the chemical derivatives found in these plants. One of them, “tubatoxin,” is one of the most potent contact insecticides known.4. A list of the groups of organic chemicals tested for their toxic action on Aphis rumicis and the eggs of Selenia tetralunaria is given. A more detailed account is given for each group of the relationships between chemical constitution and insecticidal action. It is shown that the substitution of certain radicals in the benzene ring profoundly affects toxicity, but that toxic action depends not only upon the radicals but the number substituted and in certain cases upon their relative position.5. 3 : 5-Dinitro-o-cresol is shown to have a most powerful ovicidal effect.6. An examination of the toxicity of the fatty acids is made. It is shown that as the series is ascended toxicity increases up to undecylic acid, after which it declines.

Description: 1. The toxicity of 3:5-dinitro-o-cresol and its sodium salt to the eggs of several species of moths has been determined under laboratory conditions. Both substances are toxic to eggs of the species tested at concentrations varying from 0·1 to 0·025 per cent.2. With eggs of some insects, hatching is not entirely prevented by the action of low concentrations of dinitro-cresol and sodium dinitrocresylate, but the majority of the larvae which emerge succumb within a few hours.3. The eggs of “red spider” are very resistant to the action of dinitrocresol.4. At equivalent concentrations, dinitro-cresol and sodium dinitro-cresylate have approximately the same toxicity to insect eggs.5. Washing eggs with water after spraying has no appreciable effect on the toxicity of dinitro-cresol, if the liquid is first allowed to dry on the eggs. Sodium dinitro-cresylate is more affected by washing after spraying.6. Field experiments on apples and black currants with spray fluids containing dinitro-cresol at a concentration of 0·25 per cent. and sodium dinitro-cresylate at equivalent concentration showed that both materials were completely effective against Psylla and Aphis eggs and greatly reduced the numbers of caterpillars. There was no evidence of any effect on Capsid eggs.7. Both fluids had a cleansing effect on the bark of the trees, killing algae, lichens, etc.; they caused no injury to the trees themselves. The results demonstrate the practicability of using dinitro-cresol and sodium dinitro-cresylate as winter spray fluids on dormant trees and bushes under field conditions.

Description: (1) An aerobic coccus has been obtained from cultures of the motile butyric acid bacillus under conditions which exclude the possibility of contamination.(2) Descriptions of the coccus and the bacillus are given.(3) The coccus does not fix nitrogen in soil extract containing dextrose.

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: 1. Two basic slags differing widely in solubility and phosphate content have been treated for long periods with boiling ammonium chloride solution.2. The low-grade slag lost 70 per cent. of the total lime and very little phosphoric acid; a residue with nearly 40 per cent. phosphate was obtained from an 18 per cent. slag.3. The high-soluble slag also lost a large percentage of the total lime but large amounts of phosphoric acid were also found in solution. The residue from the 30 per cent. slag after 24 hours' treatment contained nearly 46 per cent. phosphate.4. It is shown that a silico-phosphate is present in the high-soluble slag, but not in the low-grade slag.5. The solubility in citric acid of the phosphates in the various residues has been determined.6. The value of basic slags in supplying exchangeable calcium is discussed.7. The effect of hydrofluoric acid on the slag residues has been investigated.8. Experiments with fluorspar slags are described which confirm the view that the phosphate present is fluorapatite of very low solubility in citric acid.

Description: Some of the factors affecting the rate of loss of water from a drying system are shortly reviewed. These factors fall into two groups: (1) the drying system itself, and (2) the environmental conditions. The second group may include (a) diffusion of water vapour through the air, (b) bulk air movements due to (i) temperature gradients between different parts of the drying vessel, (ii) temperature lowering of the drying mass itself due to evaporation, (iii) lower density of moist air, (iv) inevitable disturbances introduced by experimental conditions such as weighing or movement of apparatus, (v) the geometry of the system. It is shown that of the external factors the most important are (2 (a)), (2 (b) (i)) and (2 (b) (ii)); (2 (b) (iv)) may produce irregularities in the rate curves of airdry granular materials; (2 (b) (iii)) and (2 (b) (v)) appear to have little or no effect.

Description: 1. Percentages of fat, solids not fat and protein were determined in over 700 samples of mixed milk from 15 herds during 1925–26. In the case of fat content, nine herds produced one or more samples below 3 per cent., one herd recording 25 per cent, of samples below this limit. With regard to solids not fat, twelve herds produced milk containing less than 8·5 per cent, on one or more occasions, the highest percentage of deficient samples recorded being 40.2. Frequency distributions of fat, solids not fat and protein percentages in the samples analysed, are given, together with standard deviations, and mean percentages with probable errors for these three constituents.3. Correlation tables of fat with solids not fat, and protein with solids not fat have been prepared, and graphs illustrating the variations are given.

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: (1) The ammonia formed in water-logged soils was present mostly in the soil sediment. The surface water contained only a very small portion of the total amount produced.(2) Added ammonia was in a similar manner retained mostly in the soil itself. It could not be leached out by extraction with water nor volatilised with increase of temperature. There is evidence to show that the ammonia exists in the soil as an exchangeable base.(3) On allowing the soils to dry out the ammonia disappeared rapidly and corresponding amounts of nitrates were formed. Very little ammonia was lost by volatilisation.(4) The production of ammonia took place even in presence of volatile antiseptics. The reaction was shown to be brought about by a deaminase.(5) Studies with a number of proteins and ammo acids showed that only very simple amino compounds (glycine aspartic acid and asparagine) were deaminised. Witte's peptone, which contains amino acids, was also attacked.(6) An active preparation of enzyme was extracted from the soil with an aqueous solution of glycerin saturated with toluene.(7) Significant deaminising action was shown by the enzymes from cultures of the mixed microflora of the soils.(8) By acting on amino bodies that are otherwise resistant to biological action the deaminase probably helps to release readily available plant food. Its action should be of great importance in tropical swamp soils.

Description: All Cows. It is proposed, in dealing with this question, to follow the same lines as in the previous Part—namely, to describe the effect as found from all the Norfolk records (comparing the results, where possible, with those found in the case of Penrith) and then to treat the various breeds, and high and low yielders separately, in order to bring out any peculiarities that may exist as regards those groups.It has already been seen that, as would be expected, the length of the S.P. very largely influences the length of the lactation, and it would seem probable on the face of it, that as pregnancy progresses the milk flow declines; this latter is dealt with in Section B of this Part, but we are here concerned with the total effect of both of these on the yield of milk in the lactation.

Description: 1. As a result of soaking in water at body temperature (38° C), foods show variations in swelling ranging from approximately 10 per cent. to 260 per cent.2. The volumes of equal weights of different foods after soaking also vary within wide limits. The percentages of moisture in the soaked foods show corresponding variations, being in some cases as high as those found in roots or green fodder.3. These facts have led the authors to put forward a new conception of “bulk” in assessing the value of a ration.4. Feeding experiments have been carried out to determine how far this factor of bulk is applicable in practice.5. In the case of pigs of 40 to 80 lb. live weight, the bulk occupied by the foods did affect the quantity of food taken.6. With calves, the swelling capacity of the concentrated food did not yield any definite results so far as food consumption was concerned.

Description: Although the primary object of recording cows' milk yields is to provide a means of comparing one individual with another, it is not satisfactorily achieved when the records have been obtained, since yields are influenced to a large extent by environmental factors which vary from cow to cow. The lactation record is the result of two sets of factors—genetic and environmental—and for purposes of selection and breeding it is important to be able to make accurate allowance for the one, so as to arrive at a good estimate of the other.Leaving aside the variation due to feeding and management (which, whilst undoubtedly large, is minimised for the cows of the same herd, and which it is hardly possible to study statistically in the existing data) the chief factors operating on the lactation yield (i.e. the measurable environmental factors) are the following:(1) Season of the year; the lactation yield is influenced to a certain extent by the month of the year in which the cow calves.(2) Service; i.e. the stage of the lactation at which the cow again becomes pregnant. The interval between calving and the next fertile service is here termed the Service Period (S.P.); thus if a cow calves on June 1st, and becomes pregnant again on July 1st, her S.P. for that lactation is 30 days.

Description: The theory of the capillary behaviour of moist soil has been further amplified for the ideal case and its relationship to various soil properties considered. Over part of the moisture range which has been dealt with by other authors it is found that there are alternative forms for the water distribution. This appears to explain why some differences of opinion have been expressed regarding some of the main points presented in a previous paper.The theory is considered in relation to capillary rise in soils as well as to the problem of cohesion previously dealt with. It is shown that the moisture distribution attained by capillary rise can be inferred from simple direct measurement of the suction pressure. Various other experimental illustrations of the theoretical conclusions are introduced.

Description: The investigation which has been dealt with in this communication was essentially a continuation of earlier work carried out in 1925 and was primarily designed with the object of ascertaining whether, under greatly differing conditions in respect of soil, herbage and weather, the striking results obtained in the 1925 investigation concerning the chemical composition, digestibility and nutritive value of pasture herbage, under a system of cutting resembling the conditions of close grazing, still held good.

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: During the carrying out of the series of researches which led to the formulation of the well-known expression for calculating the starch equivalent of a feeding stuff, Kellner(1) was led to investigate the value of crude fibre in the fattening ration of oxen. For this purpose he used material which had resulted from the boiling of rye straw with an alkaline solution under pressure, the object of this treatment being to free the cellulose of the straw from incrusting substances. This fibre-rich preparation was added to a basal ration which was slightly in excess of maintenance requirements. The result produced by the addition to the basal ration of the digestible matter derived from the fibre of the treated straw was found by Kellner to be equal to that produced by the addition of an equal weight of pure starch. The conclusion was therefore warranted that the digestion products of cellulose in the ruminant organism are equal, for purposes of fat formation in the body, to those derived from the digestion of starch. This finding is given practical expression in Kellner1s formula for calculating the starch value of a feeding stuff, an equal value being attached to digestible fibre and digestible carbohydrate.It is clear that any theory which is put forward to explain the breakdown of cellulose in the ruminant tract must be compatible with the experimentally demonstrated fact that the products of such digestion of a given weight of digestible fibre are equal in nutritive value to the products derived from the digestion of the same weight of starch.

Description: The principal factors influencing the yield and quality of milk are (1) stage of the lactation period, (2) breed of the cow, (3) interval between milkings, (4) age of the cow, (5) individuality of the cow, (6) efficiency of the milker, (7) temperature and weather conditions, (8) health of the cow, (9) feeding.

Description: 1. Under the extremely humid conditions obtaining in N. Wales, with soils showing a high degree of base-unsaturation, phosphoric acid applied to permanent grassland as basic slag is fugitive in its effect.2. From profile analyses it is shown that after six to ten years added phosphoric acid is removed from the surface layers, which revert to their original phosphorus status.3. It is suggested that the phosphorus of soils may be differentiated into that of the naturally occurring stable phosphates and the phosphorus of added dressings which is, under N. Welsh conditions, unstable and removable by percolating waters.

Description: A lighting (paraffin) oil bought casually, such as is often used in paraffin emulsions for spraying, has been subjected to fractional distillation, and shown to be unsuitable as a spraying oil.Approximate solubilities at room temperature of various “oils” in solvents such as soap solutions with and without the addition of phenols, hydrogenated phenols and pyridine, have been determined. Spray fluids containing paraffin oil, benzene, and aniline in solution are economically possible, but coal tar fractions such as anthracene and creosote oils, will, owing to lack of solubility, have to be applied to plants as emulsions. Cresylic acid is the best aid to solution of paraffin oil, but is probably more injurious to foliage than the dearer, hydrogenated phenol, hexalin.Experiments have been made on the influence of temperature when using soap (sodium oleate) and gelatine as emulsifiers; rise in temperature is found to facilitate the formation of emulsions in soap solutions, but to have a much more complex effect when gelatine is the emulsifier. A possible explanation of these facts is given.

Description: An attempt has been made to ascertain the best interval between calvings, so that the cow's average weekly yield over a long period may be at a maximum. It was only possible to consider the case of the “average cow,” but it is claimed that the general principle has been established, that cows should calve at intervals of not less than a year, and not more than thirteen months; this optimum will probably be subject to a slight variation in particular cases. This is approximately the state of affairs in practice—though Norfolk farmers appear to err on the side of serving too early in the lactation, rather than too late.

Description: 1. The Valmari-Devarda method of estimating nitrates (i.e. distillation with magnesium oxide and Devarda's alloy) is unsatisfactory in presence of organic matter. Attempts to make it quantitative under these conditions by modifications of alkali and temperature proved unsuccessful.2. Two new methods for the estimation of nitrate in plant juices are described. The first depends on the use of Devarda's alloy in cold weakly alkaline solutions, the second on the reducing power of titanous hydroxide, under conditions suitable for use with plant products.

Description: 1. 670 samples of the mixed milk from 15 herds were analysed, and the average percentages of total ash, soluble ash, insoluble ash, lime and phosphoric acid are given.2. Tables showing frequency distributions are also given, with the standard deviation, mean and probable error of mean for each constituent determined.3. Various correlations of these constituents with solids not fat and protein have been prepared, and these correlations are illustrated by graphs.It is observed that the total ash falls with the solids not fat until low values of solids not fat are reached, when the ash content appears to rise. This variation is confirmed by a curve illustrating the variation in ash content of samples of individual cow’s milk. Soluble ash rises as the solids not fat falls, but the insoluble ash shows a reverse variation. Lime and phosphoric acid both fall with the solids not fat.

Description: 1. Sudan soils are very low in organic matter, the total organic carbon being usually less than 1 per cent. In the Gezira, the humus carbon is about 40 per cent, of that of the total.2. Humus preparations purified as far as possible could not be obtained ash-free. Specimens of humus from widely different sources contain nearly the same proportion of carbon.3. Humus solutions (in very dilute alkali) keep fairly well in the dark. They also keep in bright sunlight if air is excluded. The use of standard solutions for colorimetric purposes is justified if not kept too long.4. Field studies show that the humus content of good soil is greater than that of poor, and that there is a marked inverse connection between salt and humus content.5. The above conclusion does not apply to the depth distribution of these constituents. In the Gezira, the maximum humus content is found at the fourth foot and the maximum salt content is found at about the same depth.6. The total nitrogen content of the soils studied is low, usually about 0·03 per cent. About one-fifth of this is humus nitrogen, and the carbon-nitrogen ratio is about twelve to one.

Description: During recent years a growing interest has been manifested by feeders of stock in the form of cooked maize known as flaked maize, which is produced on the industrial scale by the steaming and rolling of maize grain. Following the publication of the results of an investigation into the comparative values of dry, soaked, cooked and flaked maize for pig-feeding, in which investigation the high digestibility and feeding, value of flaked maize were amply demonstrated, frequent enquiries have been received as to whether it is justifiable to assume an equal feeding value for the several brands of flaked maize which are put on the market at the present time.

Description: In a previous paper (Davies, 1926) the author studied the differences in the compositions of protoplasmic proteins of plants within a Natural Order (Leguminosae). The Natural Order Cruciferae afforded a means of developing the study in the direction not only of ascertaining differences, if any, of protoplasmic protein of plants within a genus, but also of differences possible within a species. Thus proteins were studied from the following varieties of the cabbage species (Brassica oleracea L.): Cabbage (B. oleracea var. capitata), Marrow stem kale (B. oleracea var.) from the stems and leaves separately, Kohl rabi (B. oleracea var. caulorapa). Also, the proteins from the leaves and roots respectively of white turnips (B. napo-brassica) were isolated and studied. In order to compare the protoplasmic proteins with those of seed of a plant of the same species, a globulin from rapeseed (seed of Brassica Napus L.) was prepared and analysed.

Description: 1. The moisture equivalent of pure clay preparations varies with (a) the chemical composition, (b) the method of separation if centrifuged, (c) the replaceable bases.2. The imbibitional water content also shows a close connection with the above variables.3. Good additive relationships can only be obtained from series of soils of the same nature and in some cases, if taken at the same depth. This is, at any rate in part, due to differences existing in composition and properties between clay separated from soils and subsoils.4. Pure silt fractions from different soils showed marked differences in their chemical composition and moisture equivalent.

Description: G. W. Robinson and J. O. Jones (1) have shown that humified can be distinguished from non-humified organic matter by the use of 6 per cent, hydrogen peroxide. Humified organic matter is apparently oxidizedor rendered soluble by this reagent, whilst structural organic matter is unattacked. It seems reasonable to suppose that a similar distinction might be made in the case of farmyard manure between the amorphous decomposed material and the unaltered fibre of the faeces and litter. In other words, the degree of decomposition of farmyard manure might be determined by a method similar to that suggested for the degree of humification of soil organic matter. It is recognised that farmyard manure differs somewhat from soil organic matter in that the former includes the naturally soluble constituents of the litter, faeces and urine, which are either oxidized completely or rendered soluble in the peroxide treatment. However, they may be regarded as analogous in that both have undergone putrefactive decomposition. In the present paper, humification is used as a convenient term for the processes whereby organic matter is changed to structureless colloidal material and not as implying their exact correspondence with humification in the soil.

Description: The plants worked on in this Natural Order were the Carrot (Daucus carota L.) and the Parsnip (Peucedanum sativum Benth.). Both these plants store up reserve food in their thickened root and hypoeotyl, the disposition of the tissues being similar in both “roots.” For the extractions of their proteins, members of “races ” of these plants containing the minimum amount of core and fleshiest annuli of bast were taken, healthy, uniformly well-grown specimens being selected.

Description: (1) The formation of laterite and lateritic soils in Sierra Leone has been studied and the mode of formation and the composition of these soils is described.(2) It is suggested that since the clay fraction is regarded as the most important fraction in determining the reactions of a soil the classification of laterite and lateritic soils should be based on an examination of the clay fraction. It is further suggested that where the silica/alumina ratio in the clay fraction falls below 2·0 the soil should be described as “lateritic,” and where this ratio falls below 1·33 the soil should be described as laterite.

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 results of the investigation may be summarised as follows:(1) In Egypt, during the periods of germination and increase in height of the cotton plant, the soil temperatures are rising and the amplitude of the temperature wave is at its maximum.(2) In Egypt, the maximum soil temperatures decline while the minimum soil temperatures remain constant, thus resulting in a gradual decrease in the amplitude of the daily temperature wave during the branching and flowering periods.(3) In Egypt, throughout the soil zone occupied by the roots of the plant, the temperature is the same, the amplitude of the daily temperature wave small, and the temperature is constant during the boll development and maturation periods.(4) The main effect of irrigation on soil temperatures is to reduce the amplitude of the daily temperature wave, no sudden change of temperature in the root zone taking place.(5) From a consideration of the range of air temperature in other cotton producing countries, it seems probable that the characteristics of the soil temperatures during the boll development and maturation periods are the same for all countries.

Description: Rothamsted and Indian soils were water-logged in the absence of freshly decomposing organic matter.Nitrogen changes: Water-logging resulted in:(1) A distinct increase in the free and saline ammonia content.(2) A significant though only slight diminution in the nitric nitrogen.(3) No marked loss of ammonia by volatilisation or otherwise in the gaseous form: nor considerable variation in the nitrites: nor any observable diminution in the total nitrogen.Reaction: Water-logging resulted in an increase in alkalinity; the increase in pH value was closely correlated with the corresponding increase in ammonia.Gaseous relations: Water-logging resulted in:(1) No release of any soluble reducing matter capable of absorbing dissolved oxygen.(2) No appreciable carbon dioxide production.(3) An absorption of dissolved oxygen from the surface water. An equation has been worked out expressing the concentration gradient of dissolved oxygen with depth.Bacterial numbers:From bacterial counts on water-logged soils it was found that:(1) There was significant though slight decrease in bacterial numbers on Thornton's Agar.(2) Very few colonies were obtained by plating aerobically (and fewer still anaerobically) on Giltay's Agar. None of the organisms appearing on the plates brought about any nitrate reduction in soils.(3) The total counts on gelatine plates also showed some decrease. The numbers of gelatine-liquefiers on the other hand did not vary. There was no evidence to suggest that the increased production of ammonia was due to the activity of the gelatine-liquefiers.Agency responsible for ammonia formation:The results indicate that the formation of ammonia in water-logged soils is not due to biological action. It is suggested that the action is due to an enzyme.

Description: During recent years a large number of samples of milk having a peculiar flavour have been sent to this Institute by farmers, retailers, and wholesalers of milk.The flavour is marked and has almost invariably been described as “oily.” In many instances it has been referred to as the “castor oil flavour.”Although, as would be expected, the opinions of individuals on the flavour of such samples were not unanimous the majority agreed that “oily” was an appropriate name and since this is the name by which this taint is known to the trade it is proposed to retain it.

Description: In a former communication (1) a study has been made of the influence of the stage of lactation on the yield and quality of the milk, and in the following paper a similar investigation has been made of the influence of the age of the cow on the same factors.Mackintosh (2) finds a gradual increase in yield up to the 4th or 5th lactation period, and a decrease after the 7th or 8th; thus a heifer calving at 2¾ to 3 years gives 60–70 per cent. of the amount it will produce as a mature cow; after the second calf it gives 80 per cent. and after the third 90 per cent. Tocher's results (3) show an increase from 85 per cent, of the maximum yield at 3 years to a maximum at 7½ years, and a subsequent fall to 90 per cent. at 12 years of age.

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: 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: 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: 1. Records are offered of year old cattle reared to adult weight on rations of varying content in respect to calcium, phosphorus, sodium, potassium and chlorine. Minimal requirements for growth are higher in the case of phosphorus than in the case of calcium, and a ratio of P2O5 to CaO so high as three to one is not necessarily disadvantageous. Sodium requirements for growth are very low, 2 gm. Na2O being more than sufficient. Chlorine requirements are below 5 gm. per day. A relatively high ratio of potassium to sodium is not productive of specific disease. There is no good reason to suppose that excess of basic over acidic constituents is necessary in a dietary, and cattle can grow normally to full adult weight when the usual alkaline reaction of the urine is shifted to the acid side.2. Explanation of certain observed abnormalities in calving is left open, except in the case of phosphorus deficiency, in which definitely abnormal calves may be born.3. “Aphosphorosis,” or clinically recognisable phosphorus deficiency disease, is experimentally produced, and shown to be identical with the naturally occurring South African disease Styfsiekte.4. The chemical composition of the milk of animals suffering from aphosphorosis meed not mecessarily be abnormal, but the “inorganic” fraction of the blood may drop to a quarter of the normal value even before the disease can be diagnosed clinically. Other phosphorus compounds of the blood remain normally high. Blood calcium remains practically normal.5. Vitamine deficiency of the diets had no adverse effect. Exogenous requirements of cattle for vitamines A, B, and C are so low that they are covered by a few pounds of poor quality roughage, and therefore do not enter into consideration under any natural system of cattle rearing.

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.

Description: Attention has been drawn to our ignorance concerning the nature of the proteins of green forage plants and the gap in the science of nutrition which arises thereby in trying to apply to forage plants results obtained from proteins of concentrated foods.Methods of extraction of proteins from green tissue are outlined and applied to the study of the proteins of some common representative leguminous plants.The proteins so isolated have been analysed and characterised. Proteins thus prepared were found to resemble each other closely with respect to distribution of nitrogen into three groups.Representative samples of proteins were found to differ appreciably in their content of the different diamino acids as determined by the van Slyke method, showing variation to occur in the composition of protoplasmic proteins within a natural order, which confirms the observations of other workers on seed proteins within a natural order.The occurrence of large amounts of mineral matter in the extracts from lucerne, vetch and sainfoin, but not in those of the two clovers, together with the difficulty of obtaining pure samples of proteins from the clovers, points to the slightly less nutritive properties of the latter owing to the lesser availabilities in them of both the protein and ash.The nitrogen distribution in the protein-free extracts shows the amide nitrogen to be constant but ammonia nitrogen to be variable.

Description: 1. A measure of the errors involved in the weighing of dairy cows for experimental work is presented.2. Methods of avoiding a considerable part of these errors are suggested.

Description: An account has been given of an investigation which was designed to test the efficacy of the process of ensilage in the stack for preserving hay crops which are in danger of spoiling in consequence of adverse weather conditions.The character of the ensiled crops and the weather conditions at the time of ensiling, together with the process of building the stack, have been described in detail.The results of continuous temperature readings in the stack have been given in graphical form. The significance of the two distinct temperature maxima which characterized the temperature curve has been discussed, and the importance of this method of investigation in regard to the elucidation of the processes which go on during ensilage has been emphasized.The chemical character of the “sweet” silage samples obtained from experimental bags buried in different parts of the stack has been investigated. The losses of dry matter resulting from fermentation and drainage have been determined and the changes affecting the individual constituents of the crop have been followed quantitatively. The results so obtained have been compared with similar figures referring to the process of ensilage in the tower and the clamp.It has been shown that the loss of dry matter in the “sweet” silage layers of the stack compares satisfactorily in magnitude with the losses accompanying the preservation of crops in the tower silo and is appreciably smaller than that associated with the production of “sour” silage in the clamp.

Description: 1. Healthy tubers and “primarily infected” tubers, at time of lifting, appear to be similar both in external appearance and chemical composition.2. On drying at laboratory temperature (about 60° F.) healthy tubers lose weight much more quickly than “primarily infected” tubers. In addition, the latter remain in a “hard” condition which persists even after sprouting whereas the former become soft and flabby.3. It is suggested that healthy “seed” may be separated from “primarily infected” seed on this basis.

Description: Workers on Virus Diseases of the Potato labour under a disadvantage inasmuch as they are frequently confronted with the difficulty of obtaining positive results of infection in one and the same season. Moreover, tubers resulting from a plant which has been artificially infected in one season, retain the secret of the success or otherwise of the operation until adult plants have been grown from them in the succeeding year. Any method which will sensibly curtail this long waiting period is welcome. As long ago as 1788, Joseph Webb, writing on “Curl” in potatoes, recommended that a sample of the seed-tubers intended for planting in the following season should be planted in a hot-bed before Christmas, and that if 2 per cent, or more of the plants exhibited Curl, the stock should be destroyed.

Description: Analytical data are recorded which indicate that the application of artificial fertilisers to grass land may result in considerable modifications in the mineral content of the herbage of these pastures. The constituents which appear to show the biggest variations are calcium and potassium and, to a lesser extent, phosphorus. Coupled with any marked increase in the calcium content of the herbage, there is generally to be found an increase in the percentage of nitrogen.

Description: An account is given of an investigation of the alga-flora of four English soils by means of dilution cultures of freshly gathered samples of soil from the top, second, fourth, sixth and twelfth inch depths and from the top 6 in. mixed. A counting method is described applicable to the green algae and diatoms, by means of which it is shown that these algae are distributed throughout the top 12 in. of soil, though at the sixth and twelfth inch depths they are considerably less numerous than nearer the surface. At the fourth inch depth the numbers of individuals are not significantly smaller than on the surface and may be even greater.The unmanured plot of Broadbalk wheat field was found to contain the same main species as the adjacent farmyard manure plot but was poorer in numbers of individuate. Thirty-five species are described from each plot; they seem to be divisible into two groups, the true soil forms and casual species. Of the true soil forms some grow equally well on the surface and in the lower layers, whereas others are more numerous on the surface than within the soil. The same main types were also obtained from Barnfield and from a cottage garden, but the blue-green species were less conspicuous in both of these soils.Experimental evidence is given to show that many of the algae of the soil exist in a vegetative condition rather than a resting condition. Biological notes are made on some of the more important or interesting soil species.

Description: Dried spent hops possess a high absorptive capacity, and attention is drawn to its use as a “filler” to absorb such by-products as molasses and treacle.The material possesses a high crude protein value and its ether extract is very high for a fibrous food, while the amount of crude fibre is the same as in good meadow hay. There is a high percentage of mineral matter present.The digestibility of the material has been determined by feeding with hay chaff and linseed cake meal to three sheep. The spent hops were not readily eaten and could only be included in a ration in an amount equal to one-seventh of the dry weight of the total ration.Its digestibility is low, a fifth of the crude protein and the nitrogenfree extractives, one-half of the ether extract, one-twentieth of the crude fibre and one-fifth of the total organic matter only being digestible. The production starch equivalent was 24.5.

Description: I have been asked by Professor Gregory to examine and describe two pebbles which he has collected from the pre-glacial gravel of Little Hayes, in the Crouch Valley, South-East Essex. Examined in thin section under the microscope, one of these pebbles agrees very well with the typical chert of Arngrove (Bucks) and Studley (Oxon) in size of spicules, their mineralization, their number in a given field, and the proportion of angular sand-grains.

Description: The following remarks have been suggested by the perusal of Mr. E. B. Bailey's draft of his paper on the “Subterranean Penetration by a Desert Climate”.

Description: It is admitted that the data, from which the author draws his conclusions are, taken piecemeal, scanty, hazy, and often ambiguous. The main purpose of the investigation was to examine the contention of Bonney that the phenomena of Bardon Hill might possibly be explained by assuming flow-brecciation, and also to satisfy the author's own observation of a not irregular distribution of enclaves, which seemed to him to warrant a revision of the ideas held on the relative age of the units, that go to the building of the hill. Perhaps the main quest may be summarized into—whether the Bardon Rock is to be regarded as merely compacted agglomerate or whether it is truly igneous ? With these purposes in view the groups of data given in this paper rank in order of value: 1, Field Data; 2, Macroscopic Data; 3, Microscopic Data; 4, Chemical Data. This order iolds good, because the more searching the investigation the more obscure the real issues become—befogged by the increasing insistence of metamorphic phenomena. Any conclusions drawn must satisfactorily explain the bulk phenomena of the Bardon Hill rocks and must depend on converging evidence. Where two opposing explanations are possible, the author has adopted the simpler as the more likely.

Description: The rarity of drifts in the Crouch Valley has been often remarked. The only river gravel marked in it on the Geological Survey Map, sheet I N.E., is a small patch at Little Hayes, a couple of hundred yards north of the Crouch, and 1¼ miles S.S.W. from Woodham Ferrers railway station. In the Evolution of the Essex Rivers (1922, p. 47), an analysis of the five chief constituents, based on a collection made by Mr. H. J. Nicholson, recorded some Jurassic sandstones which I regarded as probably derived from the boulder clay on hills about three miles north and north-west. A visit to the pit last year in order to obtain larger specimens of the Jurassic material yielded various cherts; one is a typical Rhaxella chert, which has not been previously recorded so far to the south-east. A thin bedded oolitic chert, which was different to any that I knew, was submitted to Mr. H. C. Sargent with the inquiry whether it might be one of the Carboniferous cherts of the Midlands. Mr. Sargent identified some of the inclusions as silicified oolitic grains, and rejected the rock as Midland Carboniferous. The specimens and slides were also kindly examined by Professor Boswell, who showed them to Mr. E. T. Dumble for comparison with the Rhaxella chert found by him in the Crag; they also did not know any similar rock. The specimens were then sent to Dr. Morley Davies, who confirmed the identity of the one specimen with the ordinary Oxford-Buckingham Rhaxella chert, and has, in the previous note, described the other as a Rhaxella chert in which the spicules are the nuclei of oolitic grains.

Description: The high temperature of the Bath springs, their saline character, and their content of radioactive substances all combine to show that the waters must rise from a great depth. If we take the average temperature of normal spring water at 50° F. and that of the Bath Springs at 120° F., this gives an excess of 70° above the normal. Accepting the usual temperature gradient in England as being 1° F. for every 64 feet of depth, this makes the position of the: ultimate source 4,480 feet below the surface. This figure must, however, be regarded as a minimum, since no allowance is here made for cooling on ascent. This is an unknown factor, and sufficient data are not available for a reliable estimate. In any case the depth is unlikely to be less than 5,000 ft. and is probably far greater. This water, then, is obviously something very unlike the ordinary surface springs fed by atmospheric waters circulating in the upper layers of the earth's crust.