ON VETERINARY CHEMISTRY. 
97 
itself with all the other branches of natural philosophy ; so that to 
well understand this division of science an acquaintance with many 
others is called for. The general laws of matter and the properties 
thereof we must be conversant with, before we venture on the con- 
fines of chemical investigation, for some of them are constantly 
opposing chemical action. 
The influence of heat, and also of electricity, must receive the 
notice of the chemist, for these much influence his operations, if 
they are not the sole cause of all the changes that present them- 
selves. Nor can he be regardless of the nature and properties of 
light, for chemical combination takes place frequently by its agency. 
It has been justly a matter of surprise to many that natural 
philosophy is not more generally taught in onr schools of medicine, 
since so many principles are illustrated by its laws. Thus we see 
many of the laws of hydraulics operating in every act of respiration, 
and in the circulation of the fluids throughout the body. The science 
of optics renders us familiar with the laws that obtain in that beau- 
tiful and delicate organ the eye, in which we have a microscope and 
a telescope so skilfully combined, that the ablest genius is baffled 
to form such an artificial apparatus ; while acoustics tell us how 
hearing is effected, which otherwise would be perplexing to most 
of us. 
Indeed, in many more instances than these could it be shewn that 
the various divisions of natural philosophy come to the aid of che- 
mistry, and chemistry, in its turn, extends its assistance to them, 
and, in one way or another, to all the useful and ornamental arts and 
manufactures: so that, in the beautiful language of Cicero, “the 
arts which have reference to human life have a natural alliance 
among themselves, and hold each other, as it were, by the hand.” 
In conclusion, let me endeavour to remove from your minds an 
erroneous impression, too prevalent, that for the purpose of study- 
ing chemistry complicated and expensive apparatus is necessary. 
Nothing can be more delusive. It is only its principles that you 
require, or can hope to be in possession of ; and these may be gained 
with an apparatus that would not cost more than a few shillings. 
A few empty Florence flasks, some strips of glass, glass tubes, 
a piece of wire coiled in a double spiral form for a stand, a lamp 
made from an ordinary phial, a wash-hand basin, a plate or two, a 
few wine glasses, and a perforated saucer, will be all that is 
necessary. I would advise every one of you to be thus furnished, 
and to subject to the test of experiment the statements which you 
may from time to time hear made ; and, if you like, repeat all the 
experiments which you see me perform. By so doing, the study of 
the science on which we are about to enter will be rendered both 
