1864] 



Dr. Child on Spontaneous Generation. 



313 



VI.. "Experimental Researches on Spontaneous Generation.'^ By 

 Gilbert W. Child_, M.D. Oxon. Communiqated by Professor 

 Phillips. Received May 26, 1864. 



(Abstract.) 



The experiments are twenty in number, and were performed during the 

 summer of 1863. The substances used were in ten experiments milk, 

 and in ten, fragments of meat and water. These were in all cases placed in 

 a bulb of glass about 2| inches in diameter, and having two narrow and 

 long necks. The experiments are divided into five series of four experi- 

 ments each. In one series the bulbs were filled with air previously passed 

 through a porcelain tube containing fragments of pumice-stone and heated 

 to vivid redness in a furnace. In the others they were filled respectively 

 with carbonic acid, hydrogen, oxygen, and nitrogen gases. In each series 

 two experiments were made with milk, and two with meat ; and each sub- 

 stance was boiled in one case, and not boiled in the other. The joints of 

 the apparatus were formed either by means of non-vulcanized caoutchouc 

 tubing, or india-rubber corks previously boiled in a solution of potash ; 

 and in every case, at the end of the experiment, the necks of the bulb were 

 sealed by the lamp. The time of boiling such of the substances as were 

 boiled varied from five to twenty minutes, and the boiling took place in 

 the bulbs, and with the stream of gas or air still passing through. The 

 substances were always allowed to cool in the same stream of gas before 

 the bulbs were sealed. The microscopic examination of the contents of 

 the bulbs took place at various times, from three to four months after their 

 enclosure. 



In every case but one in which the substance had not been boiled low 

 organisms were found, apparently irrespective of the kind of gas in which 

 they had to exist. The case in which they were not seen was that of the 

 meat enclosed in a bulb filled with nitrogen. This bulb burst apparently 

 spontaneously, and its doing so may be looked upon as a proof that in it 

 also some change had taken place most likely connected with the develop- 

 ment of organic life. Where the substances had been boiled, the results 

 were as follows : — 



1. In the carbonic acid experiments, no sign of life. 



2. In the hydrogen experiments, no sign of life. 



3. In the heated air experiments, organisms found in both cases. 



4. In the oxygen experiments, organisms found in the experiments with 

 milk. The bulb containing the oxygen and meat burst spontaneously, 

 therefore probably contained organisms. 



5. In the nitrogen experiments, organisms were found where meat was 

 used. None where milk was used. 



No definite conclusion can be drawn from so limited a range of experi- 

 ments ; but it is worthy of remark that organisms were found here under 

 the precise circumstances in which M. Pasteur states that they cannot and 



