ALBERT

Description: Li, Rb, and Cs were determined spectrographically in twenty-eight trilobites, two xiphosurida, four insects, four Crustacea, and six brachiopods. The sediments associated with fifteen trilobites were also analysed. Compared with igneous and sedimentary rocks, the trilobites were characteristically enriched in cesium relative to rubidium and potassium. Thus, the KRb ratios were normal, but the RbCs ratios were anomalously low. The evidence is considered to favour the view that cesium has been preferentially concentrated by trilobites during growth. The matrices had RbCs ratios similar to normal sedimentary rocks.

Description: The dynamical theory of the motion of a body through an inviscid and incompressible fluid has yielded three relations: a first, due to Kirchhoff, which expresses the force and moment acting on the body in terms of added masses; a second, initiated by Taylor, which expresses added masses in terms of singularities within the bòdy; and a third, initiated by Lagally, which expresses the forces and moments in terms of these singularities. The present investigation is concerned with generalizations of the Taylor and Lagally theorems to include unsteady flow and arbitrary translational and rotational motion of the body, to present new and simple derivations of these theorems, and to compare the Kirchhoff and Lagally methods for obtaining forces and moments. In contrast with previous generalizations, the Taylor theorem is derived when other boundaries are present; for the added-mass coefficients due to rotation alone, for which no relations were known, it is shown that these relations do not exist in general, although approximate ones are found for elongated bodies. The derivation of the Lagally theorem leads to new terms, compact expressions for the force and moment, and the complete expressions of the forces and moments in terms of singularities for elongated bodies. © 1956, Cambridge University Press. All rights reserved.

Description: Consider a wing-jet combination placed in a wind tunnel; the measured thrust on the wing due to a high speed jet emerging from it will require to be corrected to give the infinite stream value. This paper provides a theory of these wind tunnel corrections, and incidently establishes that the ideal thrust is almost independent of the jet exit angle. © 1956, Cambridge University Press. All rights reserved.

Description: 1. A series of simultaneous determinations of the Na, K, N, C, ash, H2O and energy retentions of calves have been made in order to test the validity of a method of estimating energy retention without recourse to respiration chamber technique. The experiments involved 72 days' calorimetric observation with six animals. A further series of fourteen experiments with sheep involving 58 days' calorimetric observation were made but are not reported in detail2. It was found that, with calves, water retention could be estimated by an indirect method from Na, K and ash metabolism without significant systematic error. The standard deviations attached to the indirect estimates appeared to be invariant with length of period. Thus, by increasing the length of the period the accuracy of the mean daily estimate of water retention could be considerably increased.3. With calves, energy retention measured indirectly from body-weight gain and the gain of ash, protein and water did not differ significantly from that determined calorimetrically by the C and N balance technique. The standard deviation of the mean daily difference fell with increasing length of period, being ± 407 Cal./24 hr. in an experiment lasting 8 days. It was calculated that experiments with four calves lasting 24 days would give results of the same precision as that obtained in a single calorimetric trial.4. The use of the ratio calorie retention/protein retention could permit the calculation of energy retention from the N metabolism of the animal. It is suggested that this method, if developed to take into account the effect of nutritional plane on the ratio, could have considerable practical value.5. It was found that cutaneous losses of K by the sheep in its skin secretions (suint) make it impossible to interpret the difference between the intake and faecal and urinary losses of K as a body gain of K and express it in terms of water. The method is not therefore suitable for the sheep.6. The difficulties involved in the application of the method to adult cattle are pointed out, particularly those that stem from the high K content of most of the foods they eat. A very high analytical accuracy is necessary if the estimates of Na and K retention are to have the necessary precision.

Description: 1. Methods of estimating water retention in the body of cattle are discussed, and it is shown that methods based on determinations of the initial and final body-water content are of low accuracy and are not suitable for the indirect estimation of fat balance over a period of 24 days.2. Analyses of tissues from young and adult cattle showed that with the exception of serum, brain, skin and bone, water content of the tissues may be predicted from the following equation:Water(g./100g.) = 0·292 Na(mg./100g.) + 0·147 K(mg./100g.).This equation shows that 1 m.equiv. of the Na of tissues is associated with more water than is 1 m.equiv. of the K.3. No differences between cattle aged from less than 1 week to more than 5 years were observed in the relationship between water and Na and K content.4. The equation applied also to the contents of the digestive tract, other than those of the abomasum which gave low results, ascribed to the presence of a high concentration of H+ ions.5. Analyses of whole foetuses for Na, K and H2O showed that their water content could be predicted accurately. The same was true of amniotic fluid, but the water content of allantoic fluid was underestimated by 50%.6. It was shown that despite the anomalous behaviour of brain, serum, skin and bone, accurate predictions of the water content of the animal could be made from simultaneous determinations of Na and K retentions, providing a correction was made for the storage of bound Na in bone.7. Data are presented which indicate that the equations apply equally well to the tissues of the sheep.

Description: 1. Selections from a cross of varieties of Triticum vulgare and T. Turgidum have been backcrossed repeatedly to the turgidum and vulgare parents and selections of turgidum and vulgare type respectively made within each series.2. The yield and morphological stability of turgidum- and vulgare-type selections from the straight cross have been compared with those of selections backcrossed up to four times to T. turgidum and T. vulgare respectively.3. In the case of backcrosses to T. Turgidum the highest yielding selections have been derived from the most frequently backcrossed material, but the vulgare-type selections from the straight cross have outyielded those from the material backcrossed to T. vulgare.4. An analysis of the yield components of the parents and of the most promising selections, in terms of ears per plant, spikelets per ear, grains per spikelet and 1000-grain weight, has shown no evidence of a combination of the characters determining the high yield of the parents in these high yielding selections.

Description: The influence of the maternal environment on the size of lambs from birth to 8 months has been studied by reciprocally crossing the large Border Leicester and the small Welsh Mountain breeds of sheep and by transferring fertilized eggs between ewes of these breeds.Ewes which lambed later in the spring gained more weight during the last 6 weeks of pregnancy than did the earlier-lambing ewes. The birth weight of the lambs was not, however, affected by either the date of lambing or the ewes' gain in weight during the last six weeks of pregnancy.Significant breed differences in gestation length were recorded; these were 144·7 days for the Border Leicester and 147·1 days for the Welsh Mountain. Border Leicester ewes carrying pure-bred Welsh lambs had an average gestation of 149·6 days, while Welsh Mountain ewes carrying pure-bred Border Leicester lambs had an average gestation of 146·0 days. From the births of ‘transferred’ lambs, it appeared that the genetically smaller lamb was a cause of a longer gestation period. On the other hand, within groups, both live weight and length of ‘cannon bone’ of the lambs at birth increased when the gestation period was longer.The maternal environment affected foetal growth when the genotype for size of the foetus was different from that of the mother. The mean live weight and ‘cannon-bone’ length of cross-bred lambs born to Border Leicester ewes were 1·08 lb. and 0·37 cm. greater at birth than those of cross-bred lambs born to Welsh ewes. Comparable figures for the maternal influence from the results of transferring eggs from one breed to the other were 1·96 lb. and 0·33 cm. On the other hand, within breeds, there was no effect on the size of the lambs at birth of variations in the size of the ewes. The length of the ‘cannon bone’, which grows relatively rapidly during the early stages of growth (an early-maturing part of the body), was less influenced by the maternal environment than the late-maturing live weight.Mature ewes produced larger lambs at birth than young ewes. The mean differences at birth in weights and in lengths of ‘cannon bone’ of the lambs born to young and mature ewes were 1·38 lb. and 0·31 cm. respectively.From these and other experiments, the conclusions were drawn that: (i) the maternal influence on the size of young at birth is greater, in the larger species which have longer gestation periods, than the effect of the genotype of the young; (ii) the maternal organism competes with the foetus for nutrients, thus limiting the size of the young at birth; and (iii) the maternal organism may also influence pre-natal foetal growth by means of some internal secretion or metabolic substance.The amount of milk consumed by the lambs had a marked effect on their live weight gains during the first half but not during the second half of lactation. Variations in milk consumption by the lambs did not affect the growth in length of their ‘cannon bones’. The influence of the post-natal maternal environment is largely exerted through the milk yield of the ewe and causes of variation in this milk yield were reflected in the post-natal maternal influence estimated in these experiments.The total milk yield of ewes was affected by their date of lambing, that of late-lambing ewes being less than the yields of ewes which lambed earlier in the season.

Description: 1. Two digestibility trials were carried out to determine the s.e. and t.d.n. of swedes, fodder beet and grass silage when fed alone and when each kind of root was fed with silage at separate feeds. In addition, fodder beet and silage were fed together at the same feed.2. The results were examined to determine if the feeding of roots and silage together in the diet, but at separate feeds, had led to any complementary effect.3. No complementary effect was found when swedes and silage were fed at separate feeds.4. A negative complementary effect was found when fodder beet and silage were fed at separate feeds.5. The s.e. and t.d.n. values of the fodder beet plus silage at each feed were significantly higher than when the two foods were given at separate feed times.6. The s.e. and t.d.n. of the swede dry matter were higher than the standard figures published. An explanation is given.7. The nutritive value of the fodder-beet dry matter was not higher than that of swede dry matter.8. The results of the digestibility trials are compared with some calculated results from a cattle feeding trial.

Description: 1. The reaction of spring and winter types of field beans and of Windsor broad beans to artificial vernalization treatments and to successional field sowing has been studied.2. The broad bean type came into flower earlier and at a lower node on the stem than any of the field bean types, and this was not affected by either vernalization treatments or successional sowing.3. The field bean types flowered at a low node when sown in winter, but in summer sowings the level of the first flowering node was much higher; the response of the winter types was more extreme than that of the spring types.4. In the summer sowings vernalized plants came into flower earlier and at a lower node than unvernalized, but in the winter sowings both vernalized and unvernalized material flowered at an equally low node.5. A convention for naming the different stems contributing to the yield was evolved, and using this it was shown that the date of sowing affected the stems produced.6. The survival of plants in the field was not found to be affected by vernalization previous to sowing.