Pasteur's Life and Researches. 25 



how in certain cases the attacks of the inimical organisms may 

 be repelled, and how we may make those which are usefully 

 disposed do work for us in the most efficient manner. If he was 

 asked how Pasteur had discovered these new fields of scientific 

 investigation he would answer that he was the first to make the 

 microscope an instrument of chemical investigation, and in so 

 doing he has rendered as much service to science as did his 

 great countryman when he introduced the balance into 

 chemistry. The President then went on to deal with the 

 experiments of Pasteur in relation to rock-crystal, with special 

 reference to the discoveries of Biot and Arago — namely that a 

 species of crystal cut in a certain direction possesses the 

 power of turning the plane of a ray of polarised light. 

 Mention was also made of the appointment of Pasteur to the 

 assistant professorship of chemistry at Strasburg, where he 

 threw all his powers and energies into his researches. Shortly 

 after his appointment he became engaged to the daughter of 

 the rector of the University, and in speaking of this event M. 

 Radot poked a piece of fun at M. Pasteur, who is his father-in- 

 law. He said : — " 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 which was to take place that day." 

 " But if," he continued, " Pasteur was thus guilty of an 

 absentmindedness 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." 



The lecturer then spoke of M. Pasteur's experiments in 

 fermentation, and stated that the great French chemist's 

 operations were such as overthrew other theories of fermenta- 

 tion, and were marked by elegance, simplicity, and exclusiveness. 

 The experiments of Pasteur during the terrible and disastrous 

 silkworm epidemic, the beneficial results which he achieved in 

 this as in other branches of medical science, were also fully 

 dealt with. 



He had still to tell his audience of one other investigation 

 in which Pasteur has been engaged. They probably guessed 



