Standard English and American texts teach that liming effects a liberation of soil potash through ionic interchange. As examples we have the statement of Hall(8): “The action of lime upon potash compounds in the soil is equally marked: as the soil water carries down the dissolved calcium bicarbonate it attacks the zeolitic double silicates in the clay and some of their soluble bases, potash among them, change place with the lime and come into solution.” Similar statements, “One of the most important effects of calcium compounds is the conversion of insoluble into soluble forms of potassium…” by Van Slyke(25) and “but it also has some power to increase the solubility of phosphorus and potassium…” by Hopkins(9), have been accepted as authoritative.

In the course of determinations of organic carbon in soils, some unexpectedly high figures suggested the possibility that free carbon in the form of fragments of coal or cinder might affect appreciably the results obtained. The soils in question were from the Coal Measure district of Flintshire, and the presence of notable amounts of coal was not surprising. Even in soils from other districts, however, it is not unusual to find small carbonaceous fragments, which are generally noticeable in the coarse sand separated in mechanical analysis. Their presence is not difficult to explain, for domestic ashes containing unburnt coal or cinders are often thrown on to the manure heap, and thus get carted on to the soil where they persist unaltered. The highest proportions of elementary carbon may be expected in heavily manured soils such as those of gardens.

In the course of an investigation into the pathological effects of excessive protein diets on sheep (1) experiments were designed to show the changes in metabolism as recorded by nitrogen balances and weight curves. The animals were placed in metabolism cages similar to those described by Wood and Woodman (2) in their digestibility trials, and a harness of the Halnan type used.

An attempt has been made to analyse the lactation yield into its two components, maximum yield and persistency; the latter has been defined as the ratio of lactation to maximum yield, and has been measured by a S.F. calculated from , where R is the mean ratio for the month of calving concerned.

Whilst, when corrections for external factors are applied, maximum and persistence are equally constant throughout the cow's life, these factors cause wider individual fluctuations with persistency; maximum yield is subject to a more rigid limit and may be largely determined by the area of the mammary gland, but persistency seems to be chiefly a nutritional factor—that is to say, it depends on the success of the mammary gland in competing with the other tissues of the body for the available nutriment. This leads to the view that persistency is higher in the dairy type of cow; it also appears to be associated with high constitution, for very definite positive selection is apparent with persistency, as compared to marked negative selection for maximum—this is attributed to pathological attrition falling more heavily on cows with high initial yield and low persistency.

1. A volumetric method for the determination of sodium which can be separated as a triple salt (uranium zinc sodium acetate) from mixed solutions is described. The reduction of the uranium with titanous chloride, upon which it depends is shown to be quantitative.

2. Calcium, magnesium, and relatively large proportions of potash do not interfere. The procedure for the removal of iron, aluminium and phosphates by gentle ignition is simple and obviates the risk of error by the introduction of sodium as an impurity in the chemical reagents necessary for precipitation methods.

3. 0.1 mg. of sodium can be determined accurately.

The results of these experiments are, on the whole, disappointing, since they have failed to reveal a reliable treatment for parasitic gastritis of sheep other than that caused by H. contortus, but they do confirm the experiments of other workers in that there are several drugs available which are more or less effective against this worm. Of these perhaps copper sulphate would seem to be in many ways the best for general use, since it is cheap and safe, and can be easily given either dry in capsules or in solution. Better results are obtained when two doses are given, and probably the interval of 7 days between the doses could, with advantage, be shortened to one or two days. The addition of sodium arsenite did not, in these experiments, increase the efficacy of the copper sulphate.

Carbon tetrachloride, given in 12 c.c. doses would seem to be effective against Haemonchus. In such doses it is rather expensive, and although in these experiments toxic symptoms were not observed, deaths from smaller doses have been recorded by others.

Tetrachlorethylene (Nema) given in capsules containing 5 c.c. gave, in most cases, good results against Haemonchus, and except in Sheep 10 reduced the egg count very considerably. It did, however, cause considerable constipation, and in a few instances post-mortem examination revealed some inflammation of the small intestine. The administration of a laxative with or shortly after the Nema therefore appears to be indicated.

1. The average carbon-nitrogen ratio for fifty British soils from widely distributed areas approximates to the figure 10: 1 given by other investigators. The range of variation is from 6·5 to 13·5: 1. Sixteen foreign samples gave C/N ratios varying from 2·0 to 23·0: 1.

2. Soils from limited areas, whether high or low in organic carbon, give approximately constant ratios, but these ratios vary from place to place according to soil, climate, etc. It is suggested that the C/N ratios may be specific.

3. The C/N ratios of arable soils do not differ appreciably from those of grassland soils. The percentages of carbon and nitrogen are somewhat higher in the grassland samples than in the arable samples.

1. The action of various forms of sulphur—ground sulphur, flowers of sulphur and colloidal sulphur—as fungicides against the hop powdery mildew (Sphaerotheca Humuli) was tested in a number of experiments.

When ground sulphur or flowers of sulphur was wetted by a soft soap solution and applied to the mildew patches in the form of a spray, the fungicidal action was always very marked and, under the conditions of the experiments, became complete with suspensions containing 5 gm. sulphur per 100 c.c. of 0·5 per cent, soft soap solution. Owing, however, to the settling of the sulphur particles during the process of spraying, the amount of sulphur actually applied to the fungus was not strictly in accordance with the strength of the suspension.

2. Striking differences in fungicidal action were obtained when gelatine or saponin were used in place of soft soap as a spreader. Spreaders of an acid nature, viz. gelatine and saponin, inhibited the fungicidal action. With alkaline spreaders other than soft soap, e.g. lime casein and soda casein and the dry-mix sulphur lime, the alkaline reaction favoured the fungicidal action of the sulphur.

1. The application of the zinc uranyl acetate method to the determination of exchangeable sodium in soils is discussed.

2. Using this method of determination, good agreement was found between the exchangeable sodium extracted by 0·5 N acetic acid and that extracted by N ammonium chloride.

3. The procedure for estimating sodium in acetic acid extracts is described, and the results for a number of typical non-saline Welsh soils are given.

1. It is suggested that the fungicidal action of sulphur upon the Erysiphaceae is due primarily to hydrolysis.

2. The presence of alkali, which brings about an acceleration of this hydrolysis, should enhance the fungicidal properties of sulphur.

3. An explanation is thus afforded of the inhibition of the fungicidal action of sulphur against the hop powdery mildew (Sphaerotheca humuli) by gelatine or saponin solutions when employed as the spreader and of the promotion of fungicidal action in the presence of soft soap and alkali casein solutions.

4. Attention is drawn to analogies between the action of sulphur upon the mildew and upon copper.

5. Current views relative to the fungicidal action of sulphur are discussed from the standpoint of the hydrolysis hypothesis.

(1) The maintenance requirement of Light Sussex cockerels has been found by a feeding trial and comparative slaughter method. The maintenance requirement found was 22.1 calories per sq. m. of surface per hour. The net energy of the ration fed (Sussex ground oats: whole dried milk = 13 : 3) was 1.8 calories per gm.

(2) A new method of determining the surface area of birds is described.

(3) The value of K in the equation area = K has been found by this method to be 9.3.

The fluctuation in the nitrate content of arable soils in southern Australia is of special significance in connection with the practice of bare fallowing as a preparation for wheat growing. In the wheat areas of Western Australia, South Australia, Victoria and the southern districts of New South Wales, fallowing is the recognised cultural basis for successful wheat production, and from a purely mechanical point of view the practice in the hands of the more skilful farmers has probably reached a degree of perfection which it would be difficult to surpass.

It has been shown that in this trial the increase in milk yield of the nine cows considered as a herd is within the limits normally expected in the case of thrice-daily milking.

The increase in the case of the heifers is below expectation, and the probable reasons for this are indicated.

The effect of three 8-hour intervals on butter-fat percentage has been studied, and it is shown that as far as the individual cows are concerned there is little difference between the number of low fats produced under thrice milking at equal intervals and twice milking at unequal intervals in the case of the herds specified. It is shown that the reason for the bulk milk of the thrice-milked cattle maintaining a high standard of fat percentage at each milking is that each individual cow maintains a fairly high level consistently at one specific milking, and that this is not the same milking for each cow.

1. The colorimetric determination of phosphoric acid in hydrochloric and citric acid extracts of soils by a method involving the evaporation of the extract, ignition and acid extraction of the residuewith either the Denigès and Fiske-Subbarow methods of colour development was satisfactory only with light soils. Clay soils gave low results owing to the presence of larger amounts of iron.

2. A method is given in which the organic matter and iron are removed by treatment with sodium permanganate and potassium ferrocyanide. The results are in good agreement with the gravimetric method.

1. Milk and butterfat production rise to about the sixth lactation, but beyond the fifth lactation the increase may be neglected.

2. The lactation of maximum production may be taken as the fifth which corresponds to 7 years of age.

3. Beyond the fifth lactation the milk and butterfat yields vary irregularly but show a downward tendency.

4. The fat yield shows either a fall or only a very small increase in the second lactation.

5. The fat percentage is highest in the first lactation, drops markedly in the second, remains fairly steady for a few lactations, though with a slight downward tendency, and then falls off in the higher lactations.

6. Results obtained by applying correction factors for either age or lactation are quite comparable and choice in the method to be used will depend largely on the original data available.

The heavy wastage occurring in many dairy herds adds importance to the question of sex ratio in cattle, and it becomes an important factor in herds where it is desired to use only home bred cattle, as in herds free from tuberculosis and contagious abortion. The information required for the present investigation was obtained from Private Herd Books, particulars being taken as to sex of calf, month of birth and whether or not it was a first calf. Herds ravaged by contagious abortion were excluded, and also others if it was considered that there might have been neglect in entering births in the private herd book.

Experiments extending over the four years, 1926–9 inclusive, have been carried out on a heavy and stony loam soil to compare rotary cultivation with normal methods for the production of a seed-bed. The work has been confined to spring-sown crops—swedes and barley—and to spring cultivations.

Rotary cultivation gives earlier and better germination of seed, followed by better early growth.

In every experiment, however, the final yield has either been no better, or else significantly below that obtained from the plots cultivated in the usual way. The barley crop gives equally good yields under the various soil cultivation treatments; although there is better germination under rotary cultivation, the plants on the remaining plots, having greater root range, throw out more tillers and thus level up the yield. The swede crop did not do so well under rotary cultivation, in spite of better early growth. In the 1926 experiments this was due to an extensive hardening or “capping” of the soil on the rotary cultivation plots but, although this effect was absent in the 1928 experiments, a reduced yield was still obtained.

(1) Previous work suggests that there are two types or degrees of foetal atrophy. In one case, so far only reported in rats, the atrophy extends to all members of a litter and produces complete sterility. This has been shown to be connected with a pathological condition of the uterine tissues brought about by the absence of vitamin E.

Even when vitamin E is in optimum supply, however, there remains a certain amount of foetal degeneration ranging from 7 to 14 per cent, which must arise from causes other than vitamin E starvation.

In the second case a partial degree of foetal atrophy has been widely observed by different workers to occur in many different classes of mammals. Average figures for this type quoted for the pig vary from about 2 to about 20 per cent, and the residual degeneration just referred to in the rat appears to be of this nature. The present investigation was carried out to determine the effect on this second type of a deficiency in the diet of protein and of calcium. Evidence is submitted to support the conclusions which follow.

(2) Partial foetal atrophy in sows is not due to a deficiency of protein in the ration.

(3) Calcium deficiency is not the major factor in producing this type of foetal atrophy though it may be a contributory cause.

The recognition of the protein-concentrated and highly digestible character of young leafy pasturage has led to proposals for conserving such herbage by artificial drying for feeding to farm animals during winter as a substitute for oil cakes. Before contemplating the adoption of such proposals on a commercial scale, however, it was necessary to demonstrate that young pasturage could be dried artificially without losing its highly digestible nature.

That this is possible is clear from the results brought forward in this communication. It has been shown that young grass does not suffer any depression in respect of digestibility when it is dried (a) at the temperature of steam, or (b) by direct heat in a kiln.

1. It is shown that results for the loss in weight of a soil on oven heating can be obtained to a very satisfactory degree of accuracy when a Hearson electrically controlled oven is used.

2. Results obtained by heating soils to temperatures ranging from 5° to 250° give smooth curves connecting loss in weight with rise in temperature; from which it is concluded that there is no sudden alteration in the structure of a soil when it is heated to 100°, and that the airdry moisture of a soil, as determined with sufficient accuracy by the usual methods, is a convenient empirical factor, but not a representation of any fundamental soil property.

3. An examination is made of the factors contributing to the observed total loss in weight when the soil is heated, and an explanation offered of the contributions made by the different types of soil water and by the soil colloids. It is found that the conclusions drawn from this discussion confirm views developed earlier with regard to the behaviour of the water in the soil, and the absence of any sharp dividing line between the different classes into which the soil water is usually divided.