ON THE VARIETIES OF VEGETABLE FOOD. 221 
motion than is absolutely unavoidable. Airis continually taken 
in by the lungs, and acts on the fatty matter, which is re-absorbed, 
and by absorbents taken into the lungs; and there the process 
goes on during the whole winter, and the animal in its winter 
residence is supplied with fuel which it prepared during the 
summer months to enable it to live during the winter. There are 
many other animals which provide large quantities of fat in fa¬ 
vourable circumstances, and the materials thus obtained are 
burnt up and consumed when the animal could not otherwise 
obtain an adequate supply of food. A case of this kind was 
met with, some time since, in Switzerland. An avalanche fell, 
and overwhelmed a cottage and some out-buildings.' Among 
the things which it covered was a fat pig, ready for the knife. 
The animal was under the snow for six or seven weeks ; at the 
end of that period it came out alive with a loss of 160 lbs. of fat, 
which it had consumed during the time it was buried. And you 
are well aware of the fact that stout, portly gentlemen can fast 
much longer, without experiencing injury, than thin, lean persons 
who have not had the same opportunity, or the same power of 
laying up provision for a rainy day. Now, gentlemen, with 
regard to nitrogenous food , I must tell you that the use of it is 
totally distinct from that of non-nitrogenous or carbonaceous 
food. If we examine the composition of human flesh, we shall 
find that it contains a certain amount of nitrogen ; and it is very 
singular, that, when we compare our own flesh with the flesh of 
sheep or oxen, the amount of nitrogen is discovered to be 
identical. But our wonder is very much increased when we 
examine the composition of vegetable products, and find some of 
them are also substantially identical with our own flesh. If I 
take a certain quantity of flour, and wash it with water, I wash 
away the starchy matter contained in it—that matter which is 
one of the elements of respiration and one of the producers of 
lat; and I shall have left in my hands a glutinous mass, of the 
consistence of bird-lime. This material is called gluten, and, 
when sufficiently washed, it represents the nitrogenous material 
of the wheaten flour. Now, gentlemen, when that is analyzed 
by the art of the chemist, strange to say, it is found to be 
identical in composition with the flesh of man, of oxen, and of 
sheep. Again, if I take the pure cheesy matter of a cheese, and 
wash away all the oily and other materials, I find that also sub¬ 
stantially identical with the gluten of wheat and the fibrine of 
flesh. If I take the fibrine of blood, and examine that, the re¬ 
sult is the same. Both in vegetables and animals, we have the 
gluten or nitrogenous .matter existing in three forms, under three 
names, though ol almost identical chemical composition. When 
insoluble in water, it is called gluten or fibrine. When soluble 
