360 Developmental History of Infusorial, Animal Life. 



nineteenth day. The result of these experiments is, that the 

 boiled solutions of organic matter made use of, exposed only 

 to air which has passed through tubes heated to redness, or 

 enclosed with air in hermetically sealed vessels, and exposed to 

 the heat of boiling water, became the seat of infusorial life ; 

 but such experiments throw no light on the immediate source 

 from whence the organisms in question were derived. I have 

 shown repeatedly, as well as numerous other observers, that 

 the air contains many kinds of organic matter, spores of 

 cryptogams, starch granules, and other vegetable fragments, 

 and probably also the eggs of many animalcules, all of which 

 are floating freely about. 



Milne-Edwards objected to the conclusions of Pouchet, 

 saying, there is no proof that the hay itself had been subjected 

 to the temperature of boiling water, it being very probable 

 that although the furnace was at that heat, the hay, which was 

 in a glass vessel and surrounded with air at rest, was not at 

 anything like that temperature. On the other hand, granting 

 that the temperature may have been reached, that would not 

 suffice for the destruction of all the germs if they were per- 

 fectly dry ; the power of resistance possessed by vegetable 

 silicated cylindrical tubes, as hay and straw, is well known. 

 T^he observations of M. Doyere prove that the Tardigrada, 

 "water-bears," when thoroughly desiccated, preserve the 

 power of reviving even after having been subjected to a tem- 

 perature of 316° F. The Vibrio tritici will maintain its vitality 

 for many years through all the vicissitudes of heat and cold. 

 I have kept wheat for ten years, and still find these animals 

 easily resuscitated; and Mr. Deane mentions a remarkable 

 fact, ec that on a particular piece of land whenever wheat is 

 grown it is always infested with Vibrio, no matter what the length 

 of time since the previous wheat crops, nor what crops have 

 been sown in the meantime." If, therefore, animals of so 

 complex a structure as these Tardigrada and Vibrios can resist 

 the action of time and temperature, there is no reason for sup- 

 posing that the germs of the simpler animalcules would be 

 destroyed by them. 



The Rev. Lord Sidney Grodolphin Osborne, in a letter filled 

 with interesting remarks on " Cholera and its germs/' which 

 appeared a few weeks ago in the columns of the Times, writes — 

 " I know from experiment that there are ' germs' containing 

 a principle of life, that will stand very strange usage, and yet 

 not have that principle destroyed. Many years since I applied 

 a certain matter to a piece of glass about four inches Bquare. 

 This has another very thin pieco cemented close over it on 

 three sides, leaving a space just sufficient for a thin stratum 

 of water between the two. It has been exposed for days to 



