The Evolution of the Sciences 



past, interpenetrate one another, and through 

 their broken-down partitions we perceive the 

 gradual growth of the Unity of Science. 



Chemistry has not evaded this general law. 

 The facts of a chemical nature known to 

 antiquity and the Middle Ages, do not, how- 

 ever numerous, deserve the name of science. 

 One may, if one likes, trace back the first 

 chemical reaction to Prometheus, the inventor 

 of fire, or to Tubal Cain, the sixth man after 

 Adam and the creator of metallurgy; but a 

 thousand reactions no more constitute chemistry 

 than a thousand words strung in a row hap- 

 hazard form a phrase or an idea. Until the 

 eighteenth century chemistry was limited to 

 a technique scattered over the useful arts; one 

 finds it in the processes of the artisan, in the 

 pharmacopoeia of the doctor, in the operations 

 of the magician, the thaumaturge, and the 

 alchemist, in the tricks of the charlatan. Pro- 

 fessional chemists were mere compilers of such 

 processes; Glaser, in 1670, defines chemistry as 

 u the art of opening compounds by operations, 

 consisting in cutting, bruising, pulverising, 

 alcoholising, scraping, sawing, precipitating, 



