396 ANNUAL OF SCIENTIFIC DISCOVERY. 



opponents of spontaneous generation go further even than this, for they de- 

 clare these dust-like animalcules Avill be blown into a closed vessel, if it con- 

 tain organic matter, but not into several open vessels, if they only contain 

 distilled water. 



31. Quatrefages is on better ground when he rejects the evidence, long sup- 

 posed to be so weighty, of parasitic animals. He refers to the modem inves- 

 tigations which have not only made the generation of these parasites intelli- 

 gible, but in many cases have demonstrated it. M. Pouchct's reply is feeble, 

 and unworthy of a physiologist of his eminence. He doubts the truth of the 

 results obtained in Germany, Italy, and Belgium : " the monopoly of which," 

 he adds, " has, by a strange anomaly, belonged to foreigners." Because 

 France has not the honor of this splendid discovery, the Frenchman begs to 

 doubt its value ! Every physiologist, however, not French, Avill be ready 

 to admit that whereas the parasitic animals formerly furnished the advocates 

 of Spontaneous Generation with their most striking illustrations, the inves- 

 tigations of Yon Siebold, Van Beneden, Kiichenmeister, Phiiippi, and others, 

 have entirely changed the whole aspect of the question, and given the oppo- 

 nents of Spontaneous Generation new grounds for believing that in time all 

 obscurities will be cleared away, all contradictions explained. 



In conclusion, I must say, that as far as regards the particular discussion, 

 M. Pouchet seems to me to have the best of it. Their objections to his 

 experiments are all set aside. If the facts are as he states them, and his 

 antagonists at present do not dispute the facts, their criticisms go for very 

 little. They have not shown it probable that any germs could have been 

 present, under the conditions stated by him. Are we, then, to accept Spon- 

 taneous Generation as proven ? By no means. It is very far from proven. 

 The massive preponderance of fact and argument against such an hypothesis 

 forces us to pause long before we accept it. What M. Pouchet has done is 

 to destroy many of the arguments against Spontaneous Generation, and to 

 have devised experiments which may finally lead to a conclusion. It is still 

 on the cards that some source of error, as yet overlooked, vitiates his experi- 

 ments ; but until that error has been detected, he must be considered to have 

 on his side the evidence of experiment, whereas we have on our side the 

 massive evidence of extensive inductions. His experiment may be conclu- 

 sive, and an exception to the general law will thereby be established. But 

 it may also, on further investigation, turn out to be illusory; some little over- 

 sight may be detected, which will rob the experiment of all its force. 



Perhaps you will ask why this suspicion should be entertained? Why 

 ought we not to accept M. Pouchet's statement with confidence, although it 

 does contradict our inductions ? The reason can only be, that the massive 

 weight of these inductions naturally predisposes the mind to believe that it 

 is more probable the experiment which contradicts them should be miscon- 

 ceived, than that they should be contradicted. Two years ago, I became 

 acquainted with an observation made by Cienkowski, the botanist, which 

 seemed finally to settle this question of Spontaneous Generation, to place the 

 fact beyond doubt, because it caught nature in the act, so to speak, of spon- 

 taneously generating. Cicnkowski's statement is as follows : If a slice of raw 

 potato be alloAved to decompose in a little water, it will be found, after some 

 days, that the starch grains have a peculiar border, bearing a strong resem- 

 blance to a cell-membrane. This shortly turns out to be a real cell-mem- 

 brane, and is gradually raised above the starch-grain, which grain then occu- 

 pies the position of a cell-nucleus. Thus, out of a grain of starch, a cdl has 



