EXPERIMENTS IN CHEMISTRY 37 



not think I exaggerate at all and my sister, Jo- 

 sephine, is entirely of my opinion." 



The compounds whose solutions had been found 

 to exercise a rotary power on the plane of polarized 

 light, had, up to that time, proved to be organic 

 compounds,— that is, compounds formed through 

 the agency of living organisms. Pasteur was led 

 to the veiw that molecular asymmetry is a pecul- 

 iarity of the compounds formed through the 

 agency of life, and that it represents a funda- 

 mental difference between the products of living 

 and non-living matter. At that time, chemists had 

 been able to produce artincally many of the chem- 

 ical substances formed by living beings. Begin- 

 ning with the synthesis of urea from its elements 

 by Wohler in 1822, organic chemists had formed 

 in the laboratory one organic compound after an- 

 other, using the simpler ones as bases or steps from 

 which to build up substances of greater and greater 

 complexity. Dessaignes, an able chemist of Ven- 

 dome, had transformed the optically inactive maleic 

 acid to malic acid and then to aspartic acid. As 

 the latter acid had been found to have the power 

 of rotating the ray of polarized light, the question 

 arose as to whether an optically inactive substance 

 had been changed into an optically active one. 



