FERMENTATION. 2G3 



lives, by extracting oxygen from the saccharine juices 

 round them? This is a question of extreme theoretic 

 significance. It was first answered affirmatively by 

 the able and conclusive experiments of Lechartier and 

 Bellamy, and the answer was subsequently confirmed 

 and explained by the experiments and the reasoning of 

 Pasteur. Berard only showed the absorption of oxygen 

 and the production of carbonic acid; Lechartier and 

 Bellamy proved the production of alcohol, thus com- 

 pleting the evidence that it was a case of real fermen- 

 tation, though the common alcoholic ferment was ab- 

 sent. So full was Pasteur of the idea that the cells of 

 a fruit would continue to live at the expense of the 

 sugar of the fruit, that once in his laboratory, while 

 conversing on these subjects with M. Dumas, he ex- 

 claimed, ' I will wager that if a grape be plunged into 

 an atmosphere of carbonic acid, it will produce alcohol 

 and carbonic acid by the continued life of its own cells 

 that they will act for a time like the cells of the true 

 alcoholic leaven.' He made the experiment, and 

 found the result to be what he had foreseen. He then 

 extended the enquiry. Placing under a bell-jar 

 twenty-four plums, he filled the jar with carbonic acid 

 gas; beside it he placed twenty-four similar plums un- 

 covered. At the end of eight days, he removed the 

 plums from the jar, and compared them with the 

 others. The difference was extraordinary. The un- 

 covered fruits had become soft, watery, and very sweet; 

 the others were firm and hard, their fleshy portions 

 being not at all watery. They had, moreover, lost a 

 considerable quantity of their sugar. They were after- 

 wards bruised, and the juice was distilled. It yielded 

 six and a half grammes of alcohol, or one per cent, of 

 the total weight of the plums. Neither in these plums, 

 nor in the grapes first experimented on by Pasteur, 



