730 THE POPULAR SCIENCE MONTHLY. 



could still be reconciled to these views as necessarily modified subse- 

 quently to Wohler's discovery. The compounds thus formed artifi- 

 cially were still of comparatively simple structure ; and, in the nu- 

 merous transformations effected by Berthelol, in no case was the pas- 

 sage from a compound of a lower to one of a higher order. Marsh- 

 gas, methyl alcohol, and formic acid, each contained but one atom of 

 carbon ; ethylene, ethyl alcohol, and acetic acid, each contained two 

 atoms of carbon. Surely the vital force alone could build up more 

 complicated l)odies. 



ISTot so. The series of advances in the new doctrine, thus so pro- 

 pitiously begun, did not stop. New methods of investigation were 

 introduced. Questions of a different character were put to chemical 

 substances, and answers were not wanting. The interest in chemical 

 science increased, and the army of those who were to carry it forward 

 also increased. The growth of the science became proverbially rapid, 

 and, during the excitement attendant upon this development, the last 

 of the old landmarks between inorganic and organic bodies was 

 swept away ; vital force, as far as it was directly concerned in the 

 formation of organic bodies, lost prestige. Both classes of bodies 

 were found to be subject to the same fixed laws, A chemical sub- 

 stance is a chemical substance, look at it as we will. Its constituents, 

 in one case as in the other, are bound together by chemical afiinity, 

 simply and alone. Whatever the conditions may be which surround 

 the formation of organic bodies in the animal or vegetable organism, 

 the final combination of the atoms, necessary to the formation, is 

 brought about by chemical afiinity. Although we cannot reproduce 

 these conditions outside of the body, we can in so far imitate them 

 that the same kind of combination will take place. We have a-t our 

 command at present many means for the building up of the most 

 complicated organic bodies fiom the simplest. Some of these are 

 easily understood, and were discovered as the result of strict logical 

 deduction ; others are still inexplicable, and were discovered by acci- 

 dent. We can pass readily from one hydrocarbon to another, adding 

 carbon-atoms to an extent which, theoretically at least, is unlimited; 

 from one acid to another of higher order ; from alcohol to alcohol ; 

 from alcohol to acid ; from acid to hydrocarbon ; from hydrocarbon 

 to acid, through all the normal series of organic compounds. So great 

 is our power in this direction, that it is possible to produce any mem- 

 ber of any regular series of organic compounds from marsh-gas as a 

 starting-point, or from any other member whatsoever. But marsh-gas 

 can be indirectly produced from its elements, carbon and hydrogen; 

 hence, we have the possibility given of preparing artificially by far the 

 greater number of organic compounds. This number includes many 

 of those substances which are formed in the animal or vegetable or- 

 ganism. 



The formation of urea and formic acid has been alluded to. With- 



