Deaar Faldage: If I remember correctly, Pasteur discovered optical isomerism, and made
several of the original contributions thereto. I'll try to see if I can find anything worth
posting.

The sites I found were rather volminous to quote from, you can copy and paste from this:

1.Optical isomerism - Wikipedia - ... First discovered by Louis Pasteur in the nineteenth
century, the study of optical isomerism is called stereochemistry. Optical isomers ...
http://www.wikipedia.org/wiki/Optical_isomerism search within this site

2.Stereoisomerism - ... Optical Isomerism. ... the plane of polarised light and this was known as
optical activity. Louis Pasteur discovered that when 2,3-dihydroxy (tartaric) acid was ...
http://www.users.globalnet.co.uk/~freya01/stereoisomerism.htm

3.ISOMERISM AND STEREOCHEMISTRY Jack DeRuiter I. Basic Principles (PDF) - ...
Pasteur further demonstrated that the left- and right-handed crystals were mirror images of each
other ... Figure 3. Tetrahedral geometry and optical isomerism III ...
http://www.auburn.edu/~deruija/pdastch1.pdf