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.

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.

(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.

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.

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.

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.

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.

(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.

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.

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.

(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, P2O5 and 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.

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.

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.

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.

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.

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.

(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

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.

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.

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.