454 MICHEL EUGENE CHEVREUL. 



At the very first, Chevreul devoted much attention to the investi- 

 gation of the coloring matters in dj'e-woods, not because the subject 

 was at that time in the line of his duty, but, apparently, because of 

 the facility with which the materials could be procured. It has long 

 been a maxim of the French chemists, that it is well for beginners in 

 research to work upon some technical product, such as can readily be 

 obtained at a manufactory, since by so doing much of the trouble and 

 cost of procuring materials fit for investigation may be avoided. The 

 results of several of these early investigations were valuable additions 

 to scientific knowledge. It was Chevreul who discovered brazilin, 

 white-indigo, and hti;matoxylin, — also creatin. But by far the most 

 noteworthy of his works at this period was the classical research on 

 the composition of fats, which was published in book form in 1823. 

 He had been actively engaged in studying this subject during the 

 years 1811 to 1820. Of this research chemists have always held one 

 opinion, namely, that it was masterly. Hermann Kopp says of it, 

 in his Geschichte der Cheraie, " Chevreul's work on the fats is a 

 model of a complete and exhaustive research in organic chemistry." 

 It may well be said of it, that it gave to the world a new source of 

 power, akin to those gained by the investigation of the properties of 

 steam and of electricity. A great flood of light was thrown upon a 

 matter of extreme darkness. By mere force of its clearness, the 

 publication of this work led directly to numberless improvements in 

 the arts and in household economy. At a time when methods of 

 investigating organic substances were little known, this reseai'ch 

 brought out, as by a touch, complete, accurate, and enduring knowl- 

 edge of the composition and properties of a large and important class 

 of chemical substances, the study of which had previously been sup- 

 posed to be peculiarly difliicult. The research itself was thoroughly 

 and purely scieutilic. As Kopp has set forth, it disclosed the proxi- 

 mate and ultimate composition of the fats, both in general and in 

 particular, qualitatively and quantitatively, as well as the composition 

 of the products of the decomposition of fats ; it developed a rational 

 theory as to the chemical structure of the fats, and displayed the 

 relations which the fats bear to other chemical substances. Mean- 

 while, the processes of organic analysis which Chevreul used were 

 decided improvements on those of his predecessors. 



It is because of the purity and fulness of this particular fountain, 

 so to say, of scientific knowledge, that so many useful technical 

 applications have flowed from it. Even up to the present time it has 

 exerted an enormous influence upon all that relates to the manufac- 



