PROGRESS OF VETERINARY SCIENCE AND ART. 
83 
proposition is that furnished by the guttural pouches in the 
horse. A careful study of their structure and relations 
would never have enabled us to discover that they are 
destined to enclose air, and to act as resonant cavities. 
But as men know that sound is the result of aerial vibra- 
tions, and that bags of air in connection with a wind instru- 
ment increase the sounds produced, so is it inferred by 
analogy, that the guttural pouches perform a similar office. 
To investigate organic constitution does not lead to the 
discovery of physiological properties, and, chemically speak- 
ing, the difference in the combining proportions of oxygen, 
hydrogen, carbon, and nitrogen in many tissues, does not 
account for physiological differences. Bernard has not seized 
on a good illustration of this fact, by comparing the study 
of elementary substances in animal chemistry to the study of 
the letters forming words used in the very different kinds of 
literature. A letter in writing holds a very different standing 
in the scale of importance, to an element in an organic 
compound, and, indeed, the fallacy of such an analogy is too 
glaring to merit more than an allusion. 
Bernard very justly holds out for experiment as the basis 
of all physiological research, and demonstrates how anatomy 
serves for the explanation, a posteriori , of the phenomena 
discovered by physiological experiment. He speaks of the 
localisation of function ; and demonstrates how one function 
necessitates the co-operation of many organs, and in the 
same way an organ serves for many purposes. 
By the truly physiological method of investigation, as it 
has been termed by our learned author, the physiologist con- 
siders the living being in contact with the external medium, 
and studies the reciprocal influences resulting from their 
mutual action ; and just as he meets with new phenomena he 
attempts to attribute them to organs and tissues in which 
they will henceforth be localised. Bernard shows how he 
discovered the formation of sugar in the liver by tracing the 
phenomena attendant on the disappearance of sugar from the 
organism. Again, with regard to the pancreas, it was by 
experimentally tracing the modifications of the fatty matters 
within the intestine, that he was led to attribute them to the 
influence of the pancreatic secretion. 
A perfect knowledge of descriptive and topographic ana- 
tomy is essential for the proper performance of physiological 
experiments ; and at the same time anatomy is of little 
use unless rendered subservient to physiological experi- 
ment. 
If Bernard have so successfully combated the notion that 
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