1870.] with Recent Experiments. 491 



of the high temperature was surprising, and two hours after I had 

 added a little distilled water to the dust 1 found it to contain clearly- 

 defined and active monads and other living types. I may here 

 mention that the very warmth of the hand in which the slide is 

 held will often render active and instinct with life little unicellular 

 organisms which, on heing first examined with the microscope, 

 appear inanimate and motionless. 



On the 28th and 29th July I again examined the tubes, open- 

 ing the closed one on the latter day, and found that although the 

 number of forms in that was much less than in the one that had 

 been exposed, they were alike in character, and I showed to two 

 astonished visitors who had never seen such appearances, active 

 amoebae in water taken from both tubes. 



Here my experiments with pure distilled water terminated, and, 

 so far, they are not only confirmatory of what had been observed 

 and described by me many years since, but they satisfied me that 

 the solid floating contents of the atmosphere may be submitted to 

 an exceedingly high temperature in the dry as well as moist condi- 

 tion without exterminating the living germs ; and that when dis- 

 tilled water is added and the sediment is examined, either imme- 

 diately or after a few days' exposure, even if the air has been 

 excluded, it exhibits most of the phenomena believed by the advo- 

 cates of heterogenesis to be proper to infusions which have been 

 boiled and kept in vacuo. 



And now I have to describe a second set of experiments, which 

 may perhaps serve to throw light upon the appearance of those 

 fungi which are frequently found upon decaying substances in the 

 form of mould or mildew, and which Dr. Bastian believes he has 

 been instrumental in creating spontaneously in organic and inor- 

 ganic infusions. Two announcements recently made by the advo- 

 cates of heterogenesis influenced the direction taken by my investi- 

 gations. One was the statement contained in Dr. Bastian's 

 account of his experiment No. 5,* that he had discovered in an 

 infusion of turnip in vacuo which had been hermetically sealed five 

 days, a reticulated substance which he calls " Leptothrix ' filaments. 

 The other was the discovery by Mr. Wanklyn, the chemist, of suffi- 

 cient albuminous matter in a pint of air to render it highly probable, 

 from that circumstance alone, that the atmosphere is charged with 

 living germs. Mr. Wanklyn strangely enough cites his discovery, 

 triumphantly, as conclusive evidence of the absence of such germs, 

 inasmuch as the quantity of albuminous matter was found to be very 

 insignificant ; but Dr. Beale, one of our most experienced micro- 

 scopical observers, has expressed the view t that Mr. Wanklyn has 

 found a volume of such matter, which, insignificant as it may appear, 

 renders it highly probable that of the air tested by him " not a 



* Reported in ' Nature,' July 7. t 4 Nature,' July 28, p. 255. 



VOL. VII. 2 L 



