NATURAL AND ARTIFICIAL PERFUMES 135 



In spite of this they are very far from representing 

 uniform chemical substances; each, rather, is a mixture 

 of several different substances, some one of which, for the 

 most part, is the real odorous principle, and therefore the 

 only valuable one. 



The technical production of volatile oils having become 

 a great industry of modern times pursued with especial 

 zeal in Germany the chemists are making more and 

 more strenuous efforts to reach an understanding of the 

 intimate composition of these substances and of odorous 

 substances in general; and chemical science has attained 

 in this field the most notable and brilliant results. In this 

 matter technics and science have been obliged, as so often 

 before, to go hand in hand. The great firm of Sehimmel 

 & Co., for example, of Leipsic, manufacturers of volatile 

 oils, have had most of their products subjected to the most 

 exact scientific investigations, and in many cases light has 

 been thrown thereby upon obscure and complex points of 

 composition. 



Not a few chemists of repute have devoted all their 

 energies to this interesting field; a prominent pathfinder, 

 whose efforts were attended by unusual results, was the 

 late Professor Ferdinand Tiemann, of the University of 

 Berlin, who had most admirable and astonishing success 

 with syntheses of two of the most valuable perfumes, vanilla 

 and violet. 



Looking at the results of these investigations, as far as 

 it is possible to do so within the limits of our article, we 

 shall see that in the examination of single natural per- 

 fumes they were quite simple and comprehensible. Liebig 

 and Wohler, in their fundamental labors, had already 

 recognized the oil of bitter almonds as the aldehyde of 

 benzoic acid, and this was not only confirmed later by 

 synthetic methods, but the benzaldehyde soon became a 

 subject of technical synthesis. The aldehyde of cinnamic 

 acid was found to be the principal constituent of the 

 spicy Ceylon cinnamon and cassia oil ; and the methyl-ester 



