CHAP. r. MANORIAL RESIDUE FROM CATTLE-FOODS. 1001 



cows in-milk utilise more nitrogen and phosphates and potash than do 

 barren cows or oxen, for the former have to build up the body of the 

 calf, or to produce milk, a fluid very rich in both nitrogen and minerals. 



Again, the addition, to the ordinary bulky foods of the farm, of 

 oilcake or other concentrated food, which is rich in albuminoids 

 (nitrogenous bodies) and mineral matters, greatly enhances the value 

 of animal excreta. Thus, it is well known that one of the best modes 

 of manuring a grass field is to graze it with sheep, liberally supplied 

 with linseed cake or cotton cake. 



The average value of the fertilising matter resulting from the con- 

 sumption of different foods by farm stock has been calculated by 

 various chemists. The best known and most generally accepted valua- 

 tions are those of Sir John Lawes and Sir Henry Gilbert, which as 

 recently modified by Dr. J. A. Voelcker and Mr. A. D. Hall, 1 we quote 

 in the Table on pages 1002 and 1003. It is to be borne in mind that 

 these values fluctuate according to the market values of concentrated 

 artificial manures, but as comparative values they may be regarded as 

 permanently valid. 



They are based on the assumption that, under average conditions, and 

 after the various incidental losses by fermentation, &c., about half of the 

 original nitrogen of the food, about three-quarters of the phosphates, and 

 practically all of the potash find their way to the soil. The Table is 

 meant to be used as a basis for estimating the residual manurial value of 

 foods consumed in the last four years of a lapsing tenancy. 



But in applying them the circumstances of each case will be regarded 

 by the valuer, who will have to consider under what conditions the foods 

 have been consumed, and the care exercised in the management of the 

 dung, &c. When animals are fed on the land, whether at permanent 

 pasture or on a field of "seeds" or turnips, the manure they furnish 

 consists simply of their excreta, which are thus applied to the land with 

 the least possible loss of value, although the distribution, except in the 

 case of sheep folded, is unequal. But in arable farming the live stock 

 that can thus be kept constitutes at best but a portion of the total 

 live stock of the farm. For at least part of the year there will be 

 stock maintained at the homestead, the excreta of which are obtained 

 in the form of farm-yard manure or " dung." This material really 

 consists of the straw or litter supplied to the animals, trodden down by 

 them, and saturated with their excreta. On most farms, other than 

 purely grazing farms, this " dung " contains the greater part of the 

 manurial matter produced by the consumption of crops and of pur- 

 chased food. It, therefore, under the ordinary system of farming, 

 constitutes the great mainstay of the fertility of the farm, and it may 

 indeed be said that a very great share of the farmer's success in 

 cultivating his land depends upon the way in which he economises and 

 takes care of this very important, but very easily depreciated, portion 

 of his floating capital. This being so we feel justified in allotting 

 some considerable space to the discussion of this product. 



1 Journal of the Royal Agricultural Society, vol. Ixiii. 1902. 



