ODORS AND LIFE. 151 



ponderable relations of the latter, produce, by myriads of various 

 combinations, mvriads of substances which have no resemblance to 

 eacli other. The strange powers of the elements and the mysterious 

 forces concealed in matter make themselves known to us in a still 

 more remarkable phenomenon, to which the name of isomery is given. 

 Two bodies, thoroughly unlike as regards their properties, may present 

 absolutely the same chemical composition with respect to quality and 

 quantity of elements. " But in what do they differ ? " it may be asked. 

 They differ in the arrangement of their molecules. Coal and the 

 diamond are identical in substance. Common phosphorus and amor- 

 phous phosphorus are one and the same in substance. Now, the odor- 

 ous principles of plants offer some exceedingly curious cases of isomery. 

 Thus the essence of turpentine, the essence of lemon, that ofbergamot, 

 of neroli, of juniper, of savin, of lavender, of cubebs, of pepper, and of 

 gillyflower, are isomeric bodies, that is, they all have the same chem- 

 ical composition. Subjected to analysis, all these products yield 

 identical substances in identical proportions, that is, for each molecule 

 of essence, ten atoms of carbon, and sixteen atoms of oxygen, as de- 

 noted by their common formula, C 10 O 16 . We see how these facts 

 as to isomery prove that the qualities of bodies depend far more on 

 the arrangement and the inner movements of their minute particles, 

 never to be reached by our search, than on the nature of their matter 

 itself; and they show, too, how far we still are from having penetrated 

 to the first conditions of the action and forces of substances. Among 

 odoriferous essences placed by chemists in the class of aldehydes 

 may be named those of mint, rue, bitter almonds, anise, cummin, fen- 

 nel, cinnamon, etc. The rest are ranged in the great series of ethers, 

 which vary greatly in complexity, notwithstanding the simple uni- 

 formity of their primary elements. 



Such is the chemical nature of most of the odorous principles of 

 vegetable origin. But chemistry has not stopped short with ascer- 

 taining the inmost composition of these substances ; it has succeeded 

 in reproducing quite a number of them artificially, and the compounds 

 thus manufactured, wholly from elements, in laboratories, are abso- 

 lutely identical with the products extracted from plants. The specu- 

 lations of theory on the arrangements of atoms, sometimes condemned 

 as useless, do not merely aid in giving us a clearer comprehension of 

 natural laws, which is something of itself, but they do more, as real 

 instances prove ; they often give us the key to brilliant and valuable 

 inventions. An Italian chemist, who was then employed in Paris, 

 Piria, in 1838, w r as the first who imitated by art a natural aromatic 

 principle. By means of reactions suggested by theory, he prepared a 

 salicilic aldehyde, which turned out to be the essence of meadow-sweet, 

 so delicate and subtile in its odor. A few years later, in 1843, 

 Cahours discovered methyl salicilic ether, and showed that it is identi- 

 cal with the essence of wintergreen. A year after, Wertheim com- 



