A method is described for determining the field volume and the air space of a clod of any shape by filling its pores with a hydrocarbon oil, such as paraffin or tetralin, and determining its weight in the oil and in air before and after impregnation. The method appears to work well for clods of any moisture content.

This method is shown to give values of these volumes entirely comparable with those given by the other accurate methods described in the literature. Its accuracy for clods of Rothamsted soil, weighing between 20 and 500 g., was probably at least 1 part per thousand, i.e. 0-1%.

The method has been applied to the determination of the available water held by a soil and has been used to illustrate the effect of long-continued applications of farmyard manure to a soil in increasing the amount of available water it can hold.

Digestibility tests with poultry, and one with rabbits, on brans produced under war-time conditions led to the following conclusions:

1. Changes in war-time milling practice, brought about by the implementation of Government policy directed towards maximum production of flour for human use, at first led to the production of a fine bran, somewhat better in food value than prewar bran, and a coarse bran, of poorer quality than pre-war bran. Later, owing to dilution of the grist with barley, the quality of the fine bran deteriorated and became worse than that of prewar bran.

2. The changes noted were largely caused by the extremely efficient removal of the starch by the millers, and reflect the ability shown by the milling industry in diverting to human food supplies the maximum possible edible food material present in the wheat berry.

3. The superior efficiency of the rabbit's digestive system for dealing with fibrous foods, as compared with the fowl's, is emphasized by the differences in the amounts of digestible nutrients extracted from a given sample of coarse bran by these two classes of animals. 1 kg. of coarse bran yielded 2522 kg. cal. of metabolizable energy in the rabbit as compared with 1637 kg. cal. in the fowl.

A series of digestibility trials on fowls with a number of potato products led to the following conclusions:

1. Raw potatoes, though readily consumed by fowls when mixed with other foods, are not readily utilized, the potato starch largely escaping digestion.

2. Boiled potatoes are readily utilized by the fowl, the preliminary cooking altering the structure of the starch grain in such a way as to render the starch readily digestible.

3. The energy derived from 1 lb. of cooked potatoes is, in the fowl, equivalent to the energy derived from no less than 5 lb. of raw potatoes.

4. The food value of dried potato products is shown to be dependent upon the nature of the heat treatment to which the potatoes are subjected in the preliminary treatment of drying.

5. Dried potato slices of the type produced in sugar-beet factory driers have a value approximating that of well-boiled potatoes, both values being compared on a dry-matter basis.

The present paper deals with the composition and nutritive value of the following by-products of the pea-canning industry: (1) green pea pods; (2.) pea-pod meal resulting from the artificial drying of pea pods; (3) pea-pod silage as made in a tower silo; (4) molassed silage made in a sisalkraft silo from pea haulms with pods.

Pea pods give rise to an excellent silage provided they are tightly trampled and a means for draining off the effluent is supplied. The silage is pale yellowish green in colour and has a pleasant, vinegary smell with little or no suggestion of the presence of butyric acid. It is much relished by sheep and cattle. It is superior in digestibility to ‘green fruity’ oat and vetch silage and contains, per 100 lb., 27·5 lb. of dry matter, including 15·9 lb. of starch equivalent and 2·3 lb. of digestible crude protein. No molasses need be added during filling, since the sugar naturally present in the pods ensures a favourable fermentation.

Samples of bracken were taken at fortnightly intervals from June to November at two centres. These were separated into leaf and stem and analysed.

Larger samples were treated for the preparation of proteins and sugars by passing the bracken through a roller-mill, precipitating the protein with acid and concentrating the juice for sugars.

Chemical composition. The main points in the analyses of the whole plants were as follows, all figures quoted being on a dry-matter basis:

(1) The crude and true protein contents of young bracken in early June were high, 21 and 18%, but these fell rapidly to 10% in mid-July and finally to 3% in October.

(2) The lignin content was high throughout, rising from almost 20% in young bracken to 34% in the nearly dead material.

(3) The cellulose content followed the lignin content.

(4) In July and August the bracken contained about 10% of total sugars. A rapid fall occurred in October, and the final samples contained very little sugars.

Bracken cut in June was ensiled in various ways, and some of the products were examined for chemical composition, digestibility and palatability. The main findings were:

1. Overheated silage was moderately palatable to sheep and cattle, but its digestibility was low and it approximated to wheat or barley straw in feeding value.

2. Silage subjected to less heat was unpalatable, and in some cases was absolutely refused by sheep. The ensiled stems were preferred to the leaves. The digestibility was low but slightly better than that of the overheated silage.

3. Ensiling seriously affects the digestibility of bracken protein. In two silages none of the true protein was digestible, and in one the digestibility of this constituent was only 12·9%.

It is concluded that the ensiling of bracken is unlikely to prove profitable.