Proceedings of the British Association. 107 



glass chimney placed over it, so as to soften the glass, while the further 

 part of the tube was heated by another spirit lamp, to prevent its getting 

 cracked by the condensation of the steam. After the ebullition had been 

 kept up a quarter of an hour, the flask was allowed to cool and get 

 filled with air through the hot spiral of the second tube. When the 

 contents were quite cold, the end of this tube was hermetically sealed, 

 the part of it between the point and the spiral was heated strongly with 

 the flames, and the lamps were then withdrawn. The matrass contain- 

 ed now nothing but boiled flesh and gently ignited air. The air was 

 renewed occasionally through the second tube, its spiral part being 

 first strongly heated, its point then broken off, and connected with a 

 gasometer, which caused the air to pass onwards slowly, and escape at 

 the end of the first tube immersed in the quicksilver. The end of the 

 second tube was again hermetically closed, while the part interjacent 

 between it and the spiral was exposed to the spirit flame. By means of 

 these precautions, decoctions of flesh were preserved, during a period of 

 six weeks, in a temperature of from 14° to 20° R. (63l° to 77° F.), with- 

 out any appearance of putrefaction, infusoria, or mouldiness : on open- 

 ing the vessel, however, the contents fermented in a few days, as if 

 they had been boiled in the ordinary manner. In conducting such 

 researches, the greatest pains must be taken to render the cork and 

 junctions of the glass tubes perfectly air-tight. The following more 

 convenient modification of the experiment, but one equally successful 

 and demonstrative, was arranged by F. Schulze. The glass tubes con- 

 nected with the flask, were furnished each with a bulb at a little dis- 

 tance from the cork ; into one of which globes caustic alkaline lye being 

 put, and into the other strong sulphuric acid, air was slowly sucked 

 through the extremity of the one tube, while it entered at the other, so 

 as to renew the atmosphere over the decoction of flesh in the flask. 

 In another set of experiments, four flasks being filled with a solution 

 of cane-sugar, containing some beer yeast, were corked, and plunged in 

 boiling water till they acquired its temperature. They were then taken 

 out, inverted in a mercurial bath, uncorked, and allowed to cool in that 

 position. From one-third to one-fourth of their volume of atmospheri- 

 cal air was now introduced into each of the flasks ; into two of them, 

 through slender glass tubes kept red hot at a certain point, into the 

 other two through glass tubes not heated. By analysis it was found 

 that the air thus heated contained only 19.4 per cent, of oxygen, 

 instead of 20.8 ; but, to compensate for this deficiency, a little more air 

 was admitted into the two flasks connected with the heated tubes, than 

 into the two others. The flasks were now corked and placed in an 

 inverted position, in a temperature of from 10° to 14° R. (54|° to 63|o 

 F.) After a period of from four to six weeks, it was found that fer- 

 mentation had taken place in both of the flasks which contained the 

 non-ignited air — for, in loosening the corks, some of the contents were 

 projected with force— but, in the other two flasks, there was no appear- 



