70 THE LIFE OF PASTEUR 



tartaric acid. I long believed that that transformation was 

 impossible. This discovery will have incalculable conse- 

 quences." 



" I congratulate you," answered Biot on the second of June. 

 " Your discovery is now complete. M. de Senarmont will be as 

 delighted as I am. Please congratulate also Mme. Pasteur from 

 me; she must be as pleased as you." It was by maintaining 

 tartrate of cinchonin at a high temperature for several hours 

 that Pasteur Had succeeded in transforming tartaric acid into 

 racemic acid. Without entering here into technical details 

 (which are to be found in a report of the Paris Pharmaceutical 

 Society, concerning the prize accorded to Pasteur for the 

 artificial production of racemic acid) it may be added that he 

 had also produced the neutral tartaric acid — that is : with no 

 action on polarized light — which appeared at the expense of 

 racemic acid already formed. There were henceforth four 

 different tartaric acids : — (1) the right or dextro-tartaric acid; 

 (2) the left or laevo-tartaric acid ; (3) the combination of the 

 right and the left or racemic acid ; and (4) the meso-tartaric 

 acid, optically inactive. 



The reports of the Academie des Sciences also contain 

 accounts of occasional discoveries, of researches of all kinds 

 accessory to the history of racemic acid. Thus aspartic acid 

 had caused Pasteur to make a sudden journey from Strasburg 

 to Vendome. A chemist named Dessaignes — who was munici- 

 pal receiver of that town, and who found time through sheer 

 love of science for researches on the constitution of divers sub« 

 stances — had announced a fact which Pasteur wished to verify 

 it turned out to be inaccurate. 



One whole sitting of the Academie, the third of January, 

 1853, was given up to Pasteur's name and growing achieve- 

 ments. 



After all this Pasteur came back to Arbois with the red 

 ribbon of the Legion of Honour. He had not won it in the same 

 way as his father had, but he deserved it as fully. Joseph 

 Pasteur, delighting in his illustrious son, wrote effusively to 

 Biot ; indeed the old scientist had had his share in this act of 

 justice. Biot answered in the following letter, which is a 

 further revelation of his high and independent ideal of a scien- 

 tific career. 



"Monsieur, your good heart makes out my share to be 

 greater than it is. The splendid discoveries made by your 



