252 An EssaTj on Fat and Muscle. 
same weight. Should the cold prove very intense, and supplies of 
carbon and hydrogen in the form of food be not at hand, the store 
of fat which the animals have been accumulating in the mild 
seasons will be soon made use of to keep up the animal tem- 
perature. 
Example No. 2. — " One hundred sheep were folded by tens in 
pens, each of which was 22 feet in length by 10 feet in breadth, 
and possessed a covered shed attached to it : they were kept 
there from the 10th of October to the 10th of March. Each 
sheep consumed on an average 20 lbs. of swedes daily. Another 
hundred were folded in similar pens, but without sheds, during 
the same time, and their daily consumption of swedes amounted to 
25 lbs. each. The sequel was, that those sheep which enjoyed 
the protection of the covered sheds had increased 3 lb. each more 
than those left unprotected, although the latter had consumed 
one-fifth more food.'' * 
E.vaviple No. 3. — In the mountainous districts of Scotland, the 
necessity of artificial shelter for sheep has long been ackrxow- 
ledged — for, when the stormy season sets in, there is a necessity of 
feeding the sheep with hay, both morning and evening, the quantity 
of the fodder necessary being generally proportionate to the 
degree of cold. 
10. Rest also, as well as the necessary protection from cold, is 
an equivalent for food. The consumption of oxygen in a given 
time may be expressed by the number of respirations; it is there- 
fore obvious that in the same animal the quantity of nourishment 
required must vary with the force and number of respirations, 
and as the number of respirations is fewer in a state of rest than 
during labour or exercise, the quantity of food necessary in both 
instances must be in the same ratio. This can also be exemplified 
by the farmer's daily practice, since he is very well aware that the 
quieter an animal is kept when feeding, the quicker it fattens. 
Example No. 1. — It is uniformly found that a stall-fed cow in 
the summer will yield considerably more butter and milk than 
one fed in the field with a greater supply of food. The reason is 
obvious ; absence of oxygen ]>re vents the inspiring of so large an 
amount of oxygen as would take place in the open air. 
Example No. 2. — In the rearing of calves for veal in Holland, 
it is usual to confine them in suckling houses or pens, so narrow 
that the animal cannot turn round. The calf is fed through an 
opening in the doorway, just large enough to allow the head of 
the calf to be thrust out : as soon as he is fed, the opening is 
closed, and the animal is kept in total darkness. In this manner, 
* See Journal Royal Agnc. Soc, \o\. iv. p. 222. Professor Playfairs 
Lectures. 
