«456 Royal Society : — 



which, in the great majority of cases, is devoid of all foundation 

 in fact, so far as concerns the organisms essentially associated 

 with processes of putrefaction, \\i. Bacteria and Vihriones. The 

 means of proving this statement, based upon independent obser- 

 vations made by Professor Burdon Sanderson and myself, were 

 recently submitted to the consideration of the Eoyal Society*. 

 Before the reading of this communication I was under the im- 

 pression that almost every one of those who had taken part in 

 the controversies \\'hich had been carried on both here and abroad 

 concerning the Origin of Life ^^•ere prepared to admit, as Spallan- 

 zani had done, that the eggs or germs of such organisms as appear 

 in infusions were unable to survive when the infusions containing 

 them were raised to the temperature at which water boils. This 

 impression w-as produced in part by the explicit statements on this 

 subject that had been made by very many biologists, and also in 

 part by a comparatively recent and authoritative confirmation 

 which this view as to the destructive effects of boiling infusions 

 upon Bacteria had received. Little more than two years ago Pro- 

 fessor Huxley, as President of the British Association for the 

 Advancement of Science, recorded experiments in his Inaugural 

 Address which were obviously based upon this belief as a starting- 

 point ; and subsequently, in one of the Sectional Meetings, after 

 referring to some of my expei'iments, and to the fact that all un- 

 mistakably vital movements ceased after Bacteria had been boiled, 

 Professor Huxley addedf : — " I cannot be certain about other 

 persons, but I am of opinion that observers who have supposed 

 they have found Bacteria sur\dving after boiling have made the 

 mistake which I should have done at one time, and, in fact, have 

 confused the Browuian movements with true livimi movements." 

 Some eminent biologists do not now (in reference to the experiments 

 cited in my last communication) suggest that the organisms found 

 in the infusions were dead and had been there before the fluids 

 were boiled : they express doubts concerning that which seems 

 formerly to have been I'egarded as established, and now wish for 

 evidence to show that the germs of Bacteria and Vihriones are killed 

 in a boiling infusion of hay or turnip, as they have been proved to 

 be in " Pasteur's Solution " and in solutions containing ammonic 

 tartrate and sodic phosphate. 



With the view of removing this last source of doubt more effec- 

 tually, and also of refuting the unwarrantable J conclusion of M. 

 Pasteur, to the effect that the germs of Bacteria and Vihrionex are 

 not killed in neutral or slightly alkaline fluids at a temperature 

 of 212° P., I almost immediately after the reading of my last 

 communication commenced a fresh series of experiments. 



* See Proceedings of Royal Society, No. 141, 1873, p. 129. 



t See Report in Quart. Journ. of Microscop. Science, Oct. 1870. 



X Reasons for this opinion have been fully set forth in 'The Beginnings of 

 Life,' vol. i. pp. .374 et seq. ; or the discriminating reader may at once find my 

 justification for this expression by reading pp. 58-fi6 of M. Pasteur's memoir in 

 ' Ann. de C'him. et de Pliysique,' 1862. 



