Professor Tyndall c 



hay and turnip-juice, and 

 water of yeast, were freed from their floating matter in this way. 

 The infusions were subsequently boiled and permitted to remain 

 in pontact with the calcined air. They are quite unchanged to the 

 present hour, while the same infusions exposed to common air 

 became mouldy and rotten along ago. 



ft has been affirmed that turnip and hay-infusions rendered 

 sligli'ly alkaline are particularly prone to exhibit the phenomena of 

 spontaneous generation. This was not found to be the casein the 

 present investigation. Many such infusions have been preyjared, 

 and they have continued for months without sensible alteration. 



Finally, with regard to infusions wholly withdrawn from air, 

 a group of test-tubes, containing different infusions, was boiled 

 under a bell-jar filled with filtered air, and from which the air was 

 subsequently removed as far as possible by a good air-pump. 

 They are now as pellucid as they were at the time of their ]>repara- 

 ^' ■' ' ) months ago, while a group of corresponding 



le laboratory air have all tallen int< 



tubes exposed i 



There is still another form of experiment on which great weight 

 has been laid— that of hermetically sealed tubes. On April 6 last, 

 a discussion on the " (Term Theory of Disease" was opened before 

 the Pathological Society of London. The meeting was attended 

 by many distinguished medical men, some of whom were pro- 

 foundly influenced by the arguments, and none of whom disputed 

 the facts brought forward against the theory on that occasion. 

 The following important stinTmary of these was then given:— 

 " With the view of settling these questions, therefore, we may 



kidney, 'or liver; w-e may place it in a flask whose neck is drawn 

 out and narrowed in the blowpipe-flame, we may boil the fluid, 

 seal the vessel during ebullition, and keeping it in a warm place, 

 may await the result, as I have often done. After a variable time 

 the previously heated fluid within the hermetically sealed flask 

 swarms more or less plentifully with Bacteria and' allied organ- 

 Previous to reading this statement the author had o[)er;ited 

 upon tubes of hay and turnip-infusions, and upon twenty-one tubes 

 of beef, mackereb eel, oyster, oat-meal, malt, and potato, hermeti 

 cally sealed while boiling, not by the blowpipe, but by the far 

 more handy spirit-lamp flame. In no case was any appearance 

 whatever o^ Bacteria or allied organisms observed. The perusal 

 of the discussion just referred to caused the author to turn again 

 to muscle, liver, and kidney, with a view of varying and multiply- 

 ing the evidence. Fowl, pheasant, snipe, partridge, plover, wdd 

 duck, beef, mutton, heart, tongue, lungs, brains, sweetbread, tripe, 

 the crystalline lens and vitreous humor of an ox, herring, haddock, 

 mullet, codfish, sole, were all embraced in the experiments. There 

 was neither mistake nor ambiguity about the result. One huu- 



