VITALITY OF PUTEEF ACTIVE OEGANISMS. 199 



"found them afterwards permanently barren. In the 

 present instance, also, all the bulbs boiled for 5 hours, 

 6 hours, and 7 hours were completely sterilized. They 

 remained ever afterwards perfectly brilliant. This, with 

 one exception, was also the deportment of the group of 

 bulbs boiled for 8 hours. The exception was a neutral- 

 ized bulb of the Gruildford infusion, which became turbid 

 and covered with scum. Considering the severity with 

 which the bulb had been treated prior to charging, 

 and considering the mode of charging it, the life 

 developed could not possibly have been the product of 

 external germs. Through profound and thorough hard- 

 ening and desiccation, through defect of contact with 

 the liquid or some other cause, some germs in the 

 infusion itself had, I doubt not, been enabled to with- 

 stand the extraordinary ordeal here described. 



Was it 'the blighting influence of heat' that de- 

 prived the great majority of these 8-hour bulbs of the 

 power of spontaneous generation ? Whatever be the 

 meaning attached to such language the reply is ob- 

 vious, that the ^blighting' was the same for all the 

 bulbs ; and yet we find one of them which, when taken 

 from the boiling water, was perfectly brilliant, rendered 

 in two days muddy with organisms. Further, it was only 

 necessary to wash with perfectly sterilized distilled water 

 the adherent germs from a small bunch of hay, and to 

 inoculate the clear infusion in an 8-hour bulb with the 

 washing-water, to cause it within four-and-twenty hours 

 to become turbid throughout. To speak more definitely, 

 14 hours in the warm room were found sufficient to 

 cloud the infected 8-hour bulb with Bacteria. Thus 

 the infusion, when living germs are restored to it, shows 

 its perfect competence to develop them, and it was 

 solely the destruction of the germs which it possessed 

 before it was boiled that rendered it sterile afterwards. 



