. /. Wyman — Experim 



Art. IX.~ Experiments on the formation of Infusoria in hoikd 

 solutions of organic matter, enclosed in hermetically sealed vessels, 

 and supplied with pure air; by Jeffries Wyman, M.D., Her- 

 sey Prof, of Anatomy in Harvard College. 



Pasteur in his admirable researches on fermentation has 

 brought forward experimental evidence to show that this process 

 depends upon the presence of minute organisms in the ferment- 

 ing fluid and that the source of all such organisms is the atmo- 

 sphere. In support of this opinion he asserts, that when a fluid 

 containing organic matter in solution is put into a flask and 



'boiled two or three minutes," and supplied only with air which 

 has been filtered by passing through a tube heated to redness, 

 and the flask is then hermetically sealed, no fermentation takes 

 place, no organisms are formed, and that the contents remain 

 indefinitely without change. But if the same solution is exposed 

 to the air in its ordinary condition, it becomes filled with various 

 living forms. Out of a large number of experiments prepared 

 in the manner above described he has not known one to give a 

 aifterent result from that mentioned. ' He further states that if 

 tbe neck of the flask is drawn out into a very slender curved 

 tube of several inches in length, the contents 'boiled, and then 

 allowed to cool without the end of the tube being closed, so that 



ne air enters at the ordinary temperature, and has free access 

 w the interior of the flask, even then no fermentation takes 

 place and no organisms appear. His explanation of this is, that 

 the air which enters first, meets with the hot steam, and the spores 

 ^^ organisms contained in it are killed; while those which enter 

 ^"C tube later move more slowly and are deposited on the moist 

 '"' ■ of it without entering the body of the flask. ^ 



' i"st of the experiments given below the results have been 

 iHterent, and living organisms have made their appearance, 

 ;-i instances where even greater precautions were taken 

 'iiose mentioned by Pasteur. In order that the reader may 

 ^nderstand what precautions were taken we shall first describe 



^ °;^^^er in which the experiments were performed. 

 U.) In some instances (as in Expts. i to v, vii to xi, xin to xv, 



~'^ M, que jamais il pe m'es' 



