112 PASTEUR 



as nowadays are performed by every cook, Redi 

 proved conclusively that meat did not spontaneously 

 produce flies. Shortly afterwards Vallisnieri of Padua 

 demonstrated that fruit did not of itself give rise to 

 grubs. In fact, unless an insect deposited its egg in 

 the fruit, there were no grubs. 



The use of the microscope, however, lent a fresh 

 vigour to the believers in spontaneous generation ; 

 and, forced to relinquish the mouse and the insect, 

 they still found satisfaction in germs. In the middle 

 of the eighteenth century the doctrine was firmly 

 upheld by an English priest, one Needham, whose 

 experiments, in spite of the keen, and as we now 

 know, unanswerable criticisms of the Abbe Spallan- 

 zani, were so convincing that he was early elected 

 a Fellow of the Royal Society. From his time till 

 late in the last century, the question of the spon- 

 taneous origin of microscopic life has from time to 

 time troubled the mind of man. Pasteur, Tyndall, 

 and others have at length laid that ghost. It would 

 take too much space to discuss all the experiments 

 made to solve this question. Pasteur's work did not 

 escape the liveliest criticism ; and eventually, in order 

 to settle the matter, he appealed to the Academy of 

 Sciences to appoint a Commission to report on the 

 experiments of himself and his opponents. It is need- 

 less to say that when the Committee met and in- 

 spected the experiments of Pasteur, and listened to 

 the excuses of his critics, they pronounced absolutely 

 in favour of Pasteur. 



In 1862 Pasteur succeeded Senarmont as a member 

 of the Academy of Sciences ; and, it is interesting to 

 note, he was presented by the mineralogical section. 

 During this year he had interested himself in the 

 manufacture of vinegar, which is extensively carried 

 on in and around Orleans. He investigated the action 

 of the Mycoderma aceti, the mould whose activity 



