RECENT ADVANCES TN SCIENCE. 355 



To judge of its importance we must look at it from more than one 

 point of view. 



At the time when Huxley was sitting at the feet of Wharton Jones, 

 the teaching of the schools was largely governed by the view that the 

 animal organism, in contradistinction to the vegetable organism, was 

 essentially destructive in its chemical actions, possessing no power in 

 itself of synthetic construction. It is true that the possible synthesis 

 of organic compounds special to the animal body had long before, in 

 1828, been shown by W ohler's artificial formation of urea. It is true 

 also that Huber, in the case of bees, and Liebig, in the case of cows, 

 had already shown that wax and fat must be in part manufactured out 

 of something that was not fat. The conclusions, however, of these 

 observers were at best somewhat distant inferences from statistical 

 data; and, in any case, had not as yet made much way in the direction 

 of general acceptance. But Bernard's experiment was in the form of 

 an ocular demonstration. The glycogen which had been formed in the 

 liver could be extracted, could be seen, handled, and, if need be, tasted, 

 a result adequate to convince even a physiological Thomas. We may 

 claim for Bernard's glycogen discovery, that, as the first realistic proof 

 of the synthetic powers of the animal organism it did much to establish 

 a truth, which succeeding observations have only served to confirm and 

 extend, namely, that the animal, no less than the vegetable organism, 

 possesses synthetic powers, and that the want of prominence of these 

 in the ordinary work of the animal body is to be attributed to economic 

 reasons, and not to absence, or even scantiness of power. 



But there is another aspect from which the discovery must be viewed. 



At the time of which we are speaking, physiologists were still, as 

 they had been of old, largely under the influence of a somewhat 

 mechanical conception of the body as a collection of organs, each of 

 which had its special use or function, the unity of the body being main- 

 tained by the mutual adaptation of the constituent organs. This was 

 further developed into the view that when a use of an organ had been 

 satisfactorily made out, when a function had been made clear, all that 

 remained to be done, in the way of research, was simply to inquire how 

 far and in what ways the performance of that function was influenced 

 by changes in the rest of the body, or by external circumstances. It 

 was acknowledged, for instance, on all hands that the function of the 

 liver was to secrete bile, and physiologists in general were content to 

 look forward for future discoveries which should throw light on the 

 exact nature of the mechanism of the secretion, and on why the liver 

 secreted now more, now less bile, and to these alone without expecting 

 anything else. 



Bernard's discovery that the liver not only secreted bile but manufac- 

 tured glycogen fell on physiologists like a bolt from the blue. The 

 knowledge that the same hepatic cell was engaged both in secreting 

 bile and manufacturing glycogen, and that the sugar or other prod- 



