GREAT EPIDEMICS -ASIATIC CHOLERA. 301 



It not only suffers a marked change in its physical appear- 

 ance, but it loses its original organic properties. It becomes 

 impotent to perform the part of restorer which is imposed 

 on it. Of what nature is this corruption of the albumen ? 

 We cannot say, so long as we remain ignorant of the 

 nature of that very albumen in its normal state. In other 

 words, there will be no chance to begin the study of cor- 

 ruptions of the blood until the blood of man in sound health 

 shall be sufficiently understood, that is, until we shall have 

 established the nature of the albuminoid substances with 

 definite chemical exactness. That, for the moment, is the 

 grand desideratum of biology. Chemistry is much ad- 

 vanced, physiology is developing; that which remains 

 stationary is the region of questions making the transition 

 between these two sciences, and the answers to which, 

 perhaps of little importance to the former, would be the 

 source of most desirable illumination for the latter. Nu- 

 trition will never be explained until we shall have estab- 

 lished exactly the formula for those transformations through 

 which food passes from the moment it is dissolved in the 

 stomach until the moment it is thrown off by the various 

 emunctories under the form of products of disassimilation. 

 Such an explanation would not only give the key to those 

 difficulties in physiology which still hold savants in check, 

 but would also be of very great service in the knowledge 

 of diseases, and, to return to our direct subject, in that of 

 infectious diseases. It is therefore to the study of the albu- 

 minoid substances, and of the complex, rapid, and infinite 

 changes which they undergo in the blood, that capable ex- 

 aminers should now direct their attention. Those who un- 

 dertake it will not deserve the censure of setting out on a 

 beaten path, for they will have every thing to create, be- 

 ginning with the methods. At the present time we have 

 never yet compared, and we have not even the means of 

 comparing, in respect to the molecular elaboration that has 



