770 
PROFESSOR MORTON S 
fortunately, however, it is too commonly the case that the vete- 
rinary surgeon is not called in until the malady has been raging 
too long, and another and another stage has passed on, and 
putrefaction has commenced in the vegetable mass. Were he to 
employ ammonia now, he would at once give proof of his want 
of chemical knowledge, for the gases which are disengaged in 
this last stage of fermentation differ much from that given off in 
the first. They are the compounds of hydrogen. What, then, is 
the remedy here ? Chemistry tells us, chlorinated lime or soda. 
To Mr. Youatt — to whom veterinary science owes so much — 
we are indebted for the introduction of this remedy. It is a proof 
of his love of investigation and power of reasoning. Mr. Youatt 
advocates the chlorinated lime for cattle in doses of from 3ij 
to ^iv ; the compound resulting from which in the stomach is 
an hydro-chlorate of lime, which quickly undergoes solution. 
I have thought— but it is, I confess, a matter of but little 
moment — whether the disease designated diabetes also receives 
elucidation from chemical inquiry. The peculiar principle to 
which urine owes its characteristic properties, namely, urea, in 
its elementary constitution differs but little from sugar. At 
any rate, remove the nitrogen, and the same elements remain, 
and nearly in the same proportions, so as to form sugar. Hence 
when, from any derangement in the digestive apparatus, nitrogen 
is not eliminated, the blood then not having the constituents of 
urea in it, this principle necessarily does not exist in the urine, 
but in its place a compound resembling sugar, while, from the 
functional alteration induced in the kidneys, an abnormal fluid 
is secreted in increased quantities. 
The conjectures were numerous respecting the agent that 
contaminated the atmosphere in the neighbourhood of smelting 
works. That some poisonous substance was diffused, minute, 
perhaps, in quantity, but insidious in its influence on the or- 
ganism, was indisputable. The effects produced by it on animals 
have been known for a very lengthened period. The specimens 
before you exhibit enlargements of the knees of horses, and pe- 
riosteal exostosis of the bones of the legs of cows, with which 
was connected much constitutional disturbance. 
This has lately been demonstrated to have its origin in the 
disengagement of a new compound from the copper ore while 
undergoing fusion, consisting of arsenious acid, and sulphuric 
acid, with a little oxide of iron and nickel. 
In like manner, the air in the neighbourhood of lead works is 
impregnated with some compound of that metal; and colica 
pictonum , or lead colick, is a common consequence to animals, 
arising from their feeding on the herbage around, or drinking of 
