132 ELEMENTS OF BIOLOGY. 



allowed to remain unopened for a varying period. It only 

 remains to add, that in some of the experiments the rigour 

 of the conditions was still further increased by the substitu- 

 tion for the organic infusion of mere solutions of certain 

 salts, such as tartar emetic, phosphate of ammonia, or phos- 

 phate of soda. 



With regard to the alleged results of these apparently 

 crucial experiments, Dr Bastian asserts that in almost every 

 instance the fluid in the flask, in the course of a certain 

 time, was found under the microscope to exhibit numerous 

 living organisms, chiefly, though not exclusively, of a vege- 

 table nature. 



With regard to the value of these results, it should be 

 remarked, in the first place, that the conditions of the ex- 

 periment were such as we should, upon a priori grounds, 

 have believed to be utterly fatal to the possibility of the 

 development of life even in its humblest forms. The fluid 

 experimented on was subjected to a temperature exceeding 

 that of boiling water, and the flasks were hermetically sealed 

 at a time when they were filled with steam, so that the 

 atmospheric air was thereby excluded from them. It is true 

 that the experiments of Pasteur have shown that some of 

 the organisms of infusions — e.g.^ the bacteria — can exist 

 without free oxygen ; but there is certainly no reason to 

 believe that any living beings can thrive in a complete and 

 perfect vacuum. In the second place, it is to be noticed 

 that in spite of the fearfully deterrent conditions under which 

 the fluid in the flasks was placed, living beings are alleged 

 to have made their appearance therein nearly or quite 

 as abundantly as would have been the case if an ordinary 

 organic infusion had been taken, subjected to ordinary con- 

 ditions, and allowed an unrestrained access of air. 



In the third place, there is absolutely no proof that the 

 heat to which the fluids experimented on were subjected is 

 sufficient to kill any or all living germs. It is quite true 

 that, so far as we know, no adult organism can withstand 



