290 



SCIENCE. 



[N. S. Vol. II. No. 36. 



tliau prevailed mth his illustrious teacher 

 in whose laboratory he was working, he at 

 once began experiments to determine 

 whether this new color, so beautiful in its 

 hues, could be fixed upon textile fibers, and 

 succeeded in dyeing a strand of silk with it 

 without the aid of any mordant whatso- 

 ever. He promptly submitted his discovery 

 to Puller, of Perth, who tried the color in a 

 larger way, proving its commercial value. 

 The patents were secured and Perkin at 

 once devoted himself to the industrial pro- 

 duction of the color and, after more or less 

 difficulty, always incident to the manufac- 

 ture of a new substance, he attained com- 

 mercial success. The tar color industrj^ 

 was launched; it was immensely j)rofitable; 

 it furnished incentive to further investiga- 

 tion and experiment in similar lines; a new 

 field was opened up, and what a flood of 

 results has come from it ! In them both 

 empiricism and rationalism have been rep- 

 resented, and the addition to the number 

 of new substances whose properties and 

 constitution have been essential to the es- 

 tablishment of new theories and new laws 

 has been enormous and unprecedented in 

 all the history of chemical work. The 

 search after the production of a commercial 

 product, yielded accidentally as it were, 

 and almost empirically, the seed from which 

 this great and flourishing tree has sprung. 



For it must not be forgotten that, after 

 Perkin had obtained his oxidation product 

 of aniline and had found that some portion 

 of it was colored and could be applied to 

 the dyeing of fabrics, his study of its proper- 

 ties ended for the time being and it was not 

 until 1863 that he was able to take up this 

 subject and follow it to conclusion, estab- 

 lishing the constitution of the new com- 

 pound. 



The history of the coal tar color industry 

 is full of examples of the production of new 

 substances and new reactions by the indus- 

 try of the highest importance to the ad- 



vancement of knowledge in the domain of 

 chemistry and to the development of the 

 great theories to which, in turn, much of 

 progress both in science and technology has 

 been due. In this connection one may 

 study, with profit and interest, the very 

 able address of H. Caro* before the Berlin 

 Chemical Society, on the subject of the 'De- 

 velopment of the Coal Tar Color Industry.' 

 While very properly giving the fullest credit 

 for the scientific or rational work done in 

 this connection and the applications of it in 

 the industries, he shows many examples of 

 the iraf)ortant results attained by technical 

 or empirical methods and of the highest in- 

 terest and value to the science. He calls 

 attention to the fact that C. E. Nicholson 

 suggested to Hoffmann that pure aniline 

 would not yield aniline red, and that it 

 was not the true agent for the production 

 of this compound. A gallon of aniline with 

 a constant boiling point of 220° C. sent to 

 Hoffmann by Nicholson gave such a re- 

 sult ; while a sample of the ordinary aniline 

 of commerce, and boiling at fit-om 182° to 

 to 220°, yielded an abundant quantity of 

 color. From this Hoffmann concluded that 

 the commercial aniline contained a second 

 base which, together with aniline and ho- 

 mologous with it, entered into the reaction 

 to produce the regular result. But Hoff- 

 mannf declared that, if such an admixture 

 of bases existed, their separation by any 

 other than operations on a large scale would 

 be out of the question, a condition found by 

 other investigators. Nicholson had already 

 suggested the presence of toluidine in the 

 mixture. Hoffman tried making the color 

 with pure toluidine from tolu balsam sent 

 him by Muspratt and found that this, too, 

 gave a negative result. But upon mixing 

 the pure aniline from Nicholson in proper 



*Bericlite der Deutsclien Chemischen Gesellsohaft, 

 25, 955. 



t Bericbte der Deutschen Chemischen Gesellschatt, 

 25, 976. 



