476 



Action of Heat on Protoplasmic Life. [May 11, 



It occurred to me that it might be interesting to examine the influence 

 on pure albumen of the putrid-meat fluids that had been heated, and note 

 whether they still possessed the property of propagating life. A solution 

 was prepared by mixing the albumen of a new-laid egg with pure distilled 

 water free from life (prepared as described in my previous paper). Equal 

 volumes of this solution were placed in six small test-tubes, which had been 

 cleansed with hot vitriol and well washed with pure water. To one tube 

 two drops were added of the putrid-meat solution that had been heated to 

 100° F., to a second two drops of that heated to 212° F., to a third two 

 drops of that heated to 300° F., to a fourth an equal bulk of fluid heated to 

 400° F., and to a fifth the same quantity heated to 500° F. In the sixth the 

 albuminous solution, without any thing added, was kept for comparison. 



The tubes were sealed, and kept from the 1st of February to the 9 th. 



Results of Examination. 



Albumen 

 solution. 



Albumen so- 

 lution, with 

 putrid-meat 

 liquor, heated 

 to 100° F. 



Albumen so- 

 lution, with 

 putrid-meat 

 liquor, heated 

 to 212° F. 



Albumen so- 

 lution, with 

 putrid-meat 

 liquor, heated 

 to 300° F. 



Albumen so- 

 lution, with 

 putrid-meat 

 liquor, heated 

 to 400° F. 



Albumen so- 

 lution, with 

 putrid-meat 

 liquor, heated 

 to 500° F. 



In each drop 

 2 or 3 small 

 black vibrios, 

 moving to and 

 fro. 



Abundance 

 of life. 



Abundance 

 of life. 



Much less life 

 than in the 

 two fluids pre- 

 viously exa- 

 mined. 



In each drop 

 2 or 3 small 

 black vibrios, 

 moving to and 

 fro. 



In each drop 

 2 or 3 small 

 black vibrios, 

 moving to and 

 fro. 



These results clearly show that, at the temperatures of 100°, 212°, and 

 300° F., life and its germs had not been destroyed, whilst at 400° F. they 

 had ; for the results of the examination were in this case exactly identical 

 with those of the albumen solution itself ; and the life found was doubtless 

 introduced in the preparation of the solution, and was not due to any life 

 having remained in the fluids that had been heated. 



Although perfectly aware of the interesting researches of Professor Mel- 

 sens, proving that the most intense cold does not destroy the active power 

 of vaccine lymph, still I thought it desirable to ascertain the effect of a 

 temperature of 15° F. on well-developed germ-life, similar to that which 

 had been subjected to the action of heat. 



Some putrid-meat liquor, therefore, containing a large quantity of micro- 

 zyma and vibrios, was subjected for twenty hours to the influence of a tem- 

 perature ranging between the freezing-point of water and 1 7° below that 

 point, when the ice was melted and the liquor examined. The animalcules 

 retained their vitality, but appeared very languid, and their power of loco- 

 motion was greatly decreased. 



Two hours after melting the ice the liquor was again examined, when 

 the animalcules appeared to be as energetic as before. 



The Society adjourned over Ascension Day, to Thursday, May 25th. 



