RELATIONS TO OTHER SCIENCES 247 



The analysis of all these substances was a rather delicate task, and, 

 as is the rule in the sciences, no definitive results could be established 

 'until the methods of analysis were carried to a sufficient point of 

 exactness. Only after this preliminary work was it possible to 

 classify these innumerable compounds. Various theories then fol- 

 lowed, till at last synthesis came to complete the work that had been 

 begun. We recall the great researches of Berthelot on this subject: 

 synthesis of the proximate principles of the animal fats, of the 

 alcohols, acids, carbides (acetylene in particular), camphor, different 

 essences. The vital force accepted by Berzelius, Liebig, and Gerhardt 

 no longer existed. Though man's power was limited in so many 

 things, he could make by synthesis inert organic matter. 



Soon appears Kekule's schema giving a new orientation to organic 

 chemistry; and the synthesis of the most complicated compounds 

 is successfully attempted. Graebe and Liebermann accomplish the 

 synthesis of alizarin; and later, in a magnificent study of indigo, 

 Baeyer is able to state that the position of every atom in the mole- 

 cule of this dye has been experimentally determined. From these 

 researches issue the different syntheses of indigo. Finally Emil 

 Fischer achieves the syntheses of the sugars and so opens new hori- 

 zons to biology. 



For fifty years, the chemistry of carbon has formed a separate 

 chapter, and has presented a marvelous spectacle in its develop- 

 ment and in its important industrial applications. From the stand- 

 point of research, organic chemistry the fruitful theories of which 

 have been slowly transformed no longer finds any difficulty in 

 determining the composition of the innumerable derivatives that it 

 studies. Inorganic chemistry, on the contrary, though it has aroused 

 so many efforts to establish the qualitative and quantitative analysis 

 of its various compounds, is still far from completion. It is still in a 

 stage of evolution, in spite of the recent work of Gooch, Clarke, and 

 so many others. The reason for this is that some of the elements are 

 as yet very incompletely studied. The large number of simple bodies 

 included in inorganic chemistry increases the difficulty. 



When a good part of the atomic weights had been established, the 

 amount of effort that had to be devoted to organic chemistry caused 

 the number of researches in inorganic chemistry to decrease. To-day, 

 however, when the main lines of organic chemistry have been traced, 

 and when in place of the virgin forest, as Hofman called it, there 

 appears a complete city, beautifully laid out, the study of inorganic 

 chemistry has come again into honor. 



However, inorganic chemistry has been continuing its discoveries 

 in the mean time. A certain number of new, and for the most part 

 rare, elements have been isolated in the last thirty years. Lecoq de 

 Boisbaudran, in 1875, obtained from Asturian blende a new and 



