188 NOTES AND MEMOKANDA. 



and should discover a soluble alcoholic ferment, he (M. Pasteur) 

 would applaud his discovery, which would be very interesting, and 

 not in any way annoying. If he should arrive at conclusions contrary 

 to the principles established by M. Pasteur, the latter assures him 

 that " he would hasten to do for those conclusions what he has done 

 for Bernard's, viz. demonstrate their fallacies," and he calls upon 

 M. Berthelot to controvert his statements, not by a priori theories, but 

 by serious facts. 



On this reply M. Trecul made some observations* tending to 

 charge M. Pasteur with holding contradictory opinions in stating 

 that he adhered to his original classification of microbia into aerobic 

 or azymic, and anaerobic or zymic, while at the same time founding a 

 third class, which, according to circumstances, have the property of 

 living in air or without oxygen. M. Pasteur contented himself with 

 saying that M. Trecul's memory was at fault, and that since 1861 he 

 has always maintained the existence of the three kinds of organisms. 



Another "Reply to M. Pasteur" from M. Berthelot was read on 

 the 6th January,! in which, after some preliminary remarks, he 

 " comes to the question of the organisms which borrow from the sugar, 

 according to M. Pasteur, combined oxygen in place of the free 

 oxygen with which the air provides them in the ordinary conditions 

 of their existence." He retorts upon M. Pasteur the absence of any 

 support from " serious facts," and asserts that, on the contrary, 

 serious, positive facts prove that the " nutrition of yeast results from 

 a complex ensemble of chemical transformations, an ensemble which 

 it would be dangerous to the progress of science to simplify by the 

 apparent clearness of a pure supposition founded on a physiological 

 antithesis. A sufficient number of valuable discoveries have esta- 

 blished the reputation of M. Pasteur, so that he can give up without 

 detriment a theory so little justified by facts." 



M. Trecul subsequently laid before the Academy | a detailed 

 paper, in which he endeavoured to establish his assertions by nume- 

 rous extracts from M. Pasteur's writings. M. Trecul considers : — 



1st. That the organized ferments are only particular states of 

 more or less complicated species, which are modified according to the 

 media in which they are. 



2nd. That in place of establishing three classes of inferior organ- 

 isms, as M. Pasteur proposes, there is really only one, each species 

 being able to present one or many aerobian states, and one or many 

 anaerobian states. 



The activity of the subsequent controversy may be judged of by 

 a reference to our " Bibliography," where will be found the list of the 

 "Eeplies," "Second Replies," "Third Replies," "Fourth Replies," 

 " Last Eeplies," and further " Observations," and " Notes " of MM. 

 Pasteur, Berthelot, and Trecul, with which the subsequent numbers 

 of the ' Comptes Rendus ' abound. 



The discussion between M. Pasteur and M. Trecul was closed by 



* ' Comptes Eendus,' vol. Ixxxvii. p. 1058. 

 t Ibid., vol. Ixxxviii. (1879) p. 18. 

 t Ibid., p. 54. 



