€8 ON PUTREFACTIVE ORGANISMS. 



into its elements, and so make it ready again for the 

 purposes of life. Dr. Dallinger then went on to describe 

 some of the organisms which he has observed and examined. 

 He- said, that if they took some putrescent fluid from differ- 

 ent putrefactive material, and mixed them, then put a very 

 minute quantity of sterilized fluid on the microscope slide, 

 and put into this the point of a needle which had been 

 inserted into the mixture of putrefaction, and examined it 

 with a sufflciently powerful microscope, the fleld of view in 

 the microscope became, as it were, charged with life in an 

 instant. There were many kinds of organisms, and they 

 had many movements. There were rod-shaped organisms, 

 spiral forms, a perfectly oval form with two flagella, or 

 v/hips. Another would be like the calyx of a papilionaceous 

 flower, and have four flagella. Another would have a deli- 

 cate egg-shape, and another be shaped like a double convex 

 lens, and move with a beautiful wave motion. The fluid 

 speck seen under the microscope was densely jDeopled. 

 What were these organisms, and what their functions amid 

 the denizens of earth ? They were extremely small, and 

 the largest of them so small that one hundred millions 

 could be packed w^ithin a cube whose side was equal to the 

 diameter of a single human hair, and there were from ten to 

 twenty less than this. This group were amenable only to 

 the most powerful microscopes. It was known long ago 

 that they carried on putrefaction ; now they knew that the 

 process was a fermentation. Dr. Dallinger then went on to 

 contrast ordinary saccharine fermentation, like that of 3'east, 

 producing carbonic acid and alcohol, with the fermentation 

 produced by these saprophytic organisms, and showed 

 that both could be prevented by taking care to keep away 

 any of the germs of the fermentation, that both could be 

 arrested by the action of heat, and that both tended to 



