1850—1854 57 



finally touched to the heart, until the period of absolute mutual 

 confidence and friendship, we see rising before us the image of 

 this true scientist, with his rare independence, his good-will 

 towards laborious men and his mercilessness to every man 

 who, loving not Science for its own sake, looked upon a dis- 

 covery as a road to fortune, pecuniary or political. 



He loved both science and letters, and, now that age had 

 bent his tall form, instead of becoming absorbed in his own 

 recollections and the contemplation of his own labours, he 

 kept his mind open, happy to learn more every day and to 

 anticipate the future of Pasteur. 



During the vacation of 1851 Pasteur came to Paris to bring 

 Biot the results of new researches on aspartic and malic acids, 

 and he desired his father to join him in order to efface the sad 

 impression left by his former journey in 1838. Biot and his 

 wife welcomed the father and son as they would have welcomed 

 very few friends. Touched by so much kindness, Joseph 

 Pasteur on his return in June wrote Biot a letter full of 

 gratitude, venturing at the same time to send the only thing it 

 was in his power to offer, a basket of fruit from his garden. 

 Biot answered as follows : " Sir, my wife and I very much 

 appreciate the kind expressions in the letter you have done me 

 the honour of writing me. Our welcome to you was indeed as 

 hearty as it was sincere, for I assure you that we could not see 

 without the deepest interest such a good and honourable father 

 sitting at our modest table with so good and distinguished a son. 

 I have never had occasion to show that excellent young man 

 any feelings but those of esteem founded on his merit, and an 

 affection inspired by his personality. It is the greatest pleasure 

 that I can experience in my old age, to see young men of talent 

 working industriously and trying to progress in a scientific 

 career by means of steady and persevering labour, and not by 

 wretched intriguing. That is what has made your son dear to 

 me, and his affection for me adds yet to his other claims and 

 increases that which I feel for him. We are therefore even 

 with one another. As to your kindness in wishing that I 

 should taste fruit from your garden, I am very grateful for it, 

 and I accept it as cordially as you send it." 



Pasteur had also brought Biot some other products— a case 

 full of new crystals. Starting from the external configuration 

 of crystals, he penetrated the individual constitution of their 

 molecular groups, and from this point of departure, he then 



