24 ORGANIC SUBSTRATA OF THE ANIMAL ORGANISM. 



gators, who are often unwearyingly occupied for years together in 

 endeavouring to collect a few firm supports for the great edifice 

 of a true philosophy of nature, we do not despair of seeing our 

 work rise in simple grandeur., more durable and lasting than those 

 sophisms of natural philosophy which, passing through ages from 

 Pythagoras and Empedocles to Schelling and Hegel, have, like the 

 sand of the ocean shore, been alternately upborne by one wave 

 and engulphed by the next.* 



THE ORGANIC SUBSTRATA OF THE ANIMAL ORGANISM. 



While we admit that the general investigation of nature must 

 derive its chief support and stability from the investigation of 

 particulars ; and while we deplore the evils that have accrued 

 to the natural sciences from the premature abstractions and hazard- 

 ous generalisations, deduced from data, which are in themselves 

 correct ; we must remember that no department of natural science, 

 however limited its domain, should be entered upon without the aid 

 of certain leading maxims, and without a definite aim. These 

 must be sought by physiological chemistry in physiology, no 

 less than in general chemistry; for without these aids zoo- 

 chemistry will continue a confused mass of loosely connected 

 facts, from which every fanciful enquirer may select whatever suits 

 his views, to beguile himself or others with short-lived dreams and 

 illusions. 



The general principles and recent acquisitions of chemistry are 

 as essential to the consideration of the properties and chemical meta- 

 morphoses of animal substances, as an intimate acquaintance with 

 physiological theories is to the deeper insight into the chemistry of 

 the animal functions. It would be both inappropriate, and detri- 

 mental to this branch of science, to borrow from general chemistry 

 only such matters and facts as refer to the animal body, in order to 

 accumulate a mass of disjointed bodies, and group them together 

 simply according to their physiological import; as if we considered 

 zoo-chemical processes in a purely chemical light, depending upon 

 combination or decomposition, on chemical dualism, the theory of 

 acids and bases, &c. : we should rather adhere in our study of the 

 chemical substrata of the animal organism to the more general che- 



* If any of my readers have chanced to meet with the article, " Chemismus in der 

 Medicin," which appeared in the " Gegenwart," they have probably been struck by the 

 similarity existing between the ideas expressed in the present work and the line of thought 

 followed in that essay ; I therefore feel called upon to avow the authorship of it. 



