124 heport— 1871. 



to a liquid susceptible of entering into tliesse states ; and during the inquiry some 

 facts were observed which I wish now to lay before you. 



The first is the rapid development of germ-life. If the white of a new-laid egg 

 be mixed with water (free from life), and exposed to the atmosphere for only fifteen 

 minutes, in the months of August or September, it will show life in abundance ; 

 and to the want of a linowledge of this fact may be traced the erroneous conclu- 

 sions arrived at by several gentlemen who have devoted their attention to the 

 subject of spontaneous generation. 



An essential point in the carrying out of such an investigation, was the prepara- 

 tion of pure distilled water. In distilled water prepared hy the ordinary methods, 

 1 always found life after it had been kept for a few days ; but by employing an ap- 

 paratus thi-ougli which a gas could be passed to displace the air, and adding to tlie 

 water to be distilled a solution of potash and permanganate of potash, I obtained a 

 water which, after three or four distillations, was found to be free from life. The 

 gas emploved in the first three series was hydrogen. The water was kept in the 

 apparatus tiU wanted, to prevent any contact with air. 



Water so distilled having been kept free from life for seventeen days, was intro- 

 duced into twelve small tubes, and left exposed to the atmosphere for fifteen hours 

 when the tubes were closed. Every eight days the tubes were examined ; on the 

 first and second examination no life was observed, but the third discovered two 

 or three black vibrios in each field. 



As this slow and limited development of life might be owing to the small amount 

 of germs in the atmosphere, during the winter months a second series of experi- 

 ments was made, placing the water in the tubes near putrid meat for two hours, at 

 a temperature of 21° to 26° C. Six days after some of the tubes were examined and 

 life observed, showing that by being placed near a source of protoplasmic life, the 

 water had in two hours absorbed germs in sufficient quantity, for life to become 

 visible in one fourth the time required in tlie first experiment ; after six days a 

 slight increase of life was noticed, but no further development could be aftenvards 

 seen. 



The limited amount of life developed in pure water suggested a third series of 

 experiments, in which albumen was added to the water. In this case life appeared 

 in five days, and a considerable increase in ten. Albumen, therefore, facilitated 

 the development of life. 



The quantity of life produced in the above experiments being comparatively 

 small, some fresh water was distilled, oxygen being substituted for the hydrogen in 

 the apparatus ; and a fourth series was commenced, which resulted in showing that 

 although oxygen appears to favour the development of germs, it does not favour 

 their reproduction. 



When the weather had become much wanner and a marked increase of life in 

 the atmosphere had taken place, some of the albumen solution employed in the 

 above experiments was left exposed in tubes to its influence, when a large quantity 

 of life was rapidly developed and continued to increase, pi'oving the increase to be 

 due not merely to reproduction, but to the introduction of fresh germs. 



As no life appeared in that portion of the distilled water remaining in the ap- 

 paratus before mentioned, which was exaiiiined from time to time, whilst it ap- 

 peared in all the solutions made with it and impregnated by their exposure to the 

 atmosphere, it is obvious that gemis are necessary to the production of life. 



On the relative Powers of various Substances in preventing the Generation of 

 Animalcules, or the Development of their Germs, with spedal reference to the 

 Germ Theory of Putrefaction. By Dr. John Dougal. 



On the advantage of Systematic Cooperation among Provincial Natural- 

 Histo7'y Societies, so as to make their observations available to Naturalists 

 generally. By Sir Walter Elliot, K. C.S.I., F.L.S. 

 Sir Walter stated that he had been led to consider the subject in the prepara- 



