22 LOUIS PASTEUK. 



required nothing less than his engagement with 

 Mademoiselle Marie Laurent, daughter of the Eector 

 of the Academy. It is even asserted that on the very 

 morning of his marriage it was necessary to go to his 

 laboratory and remind him of the event that was to 

 take place on that day. But if Pasteur was thus guilty 

 of an absent-mindedness worthy of La Fontaine, he 

 proved as a husband so different from La Fontaine 

 that Madame Pasteur, when reminded of this lapse 

 of memory, receives the reminder with an indulgent 

 smile. 



But to return to the laboratory : Under the same 

 conditions of weight, temperature, and quantity of 

 solvent, Pasteur placed successively, in presence of the 

 two acids, all the substances capable of combining 

 with them. In this way he obtained right-handed 

 and left-handed tartrates of potash, of soda, of am- 

 monia, of lime, and of all the oxides properly so called. 

 He applied himself to the compounds and they are 

 numerous which deposit themselves in liquids under 

 well- determined crystalline forms. Without entering 

 into the details of these long and patient studies, it 

 may be stated generally that Pasteur proved that 

 whatever could be done with one of the tartaric acids 

 could be repeated rigorously, under similar conditions, 

 with the other, the resultant products manifesting 

 constantly the same properties, with the single differ- 

 ence already exhibited by the two acids that in the 



