570 



Presents. 



[Feb. 1, 



under that o£ boiling water. Such softened and vivified germs as are 

 on the point of passing into active life are thereby killed; others not 

 yet softened remain intact. I repeat this process well within the interval 

 necessary for the most advanced of those others to finish their period of 

 latency. The number of undestroyed germs is further diminished by this 

 second heating. After a number of repetitions, which varies with the 

 character of the germs, the infusion, however obstinate, is completely 

 sterilized. 



The periods of heating need not exceed a fraction of a minute in 

 duration. Sum them up in the case of an infusion which they have 

 perfectly sterilized ; they amount altogether to, say, five minutes. Boil 

 another sample of the same infusion continuously for fifteen or even 

 sixty minutes, you fail to sterilize it, although the temperature is higher 

 and its time of application more than tenfold that which, discontinously 

 applied, infallibly produces barrenness. 



In a few weeks I hope to bring this entire subject under the notice of 

 the Eoyal Society ; meanwhile, if you think it would interest them, I 

 should be glad if you would communicate to the Fellows this general 

 statement of the most recent results of experiment. 



Believe me, 



Ever faithfully yours, 



John TtjS^dall, 



H, Huxley, Esq,, ^ec> E.S, 



Presents received, February 1, 1877. 



Transactions. 



Calcutta : — Asiatic Society of Bengal. Journal. Vol. XLIY. Part 2, 

 No. 3 ; Vol. XLY. Part 1. No. 1 ; Part 2. No. 1, 2. 8vo. 1875- 

 76. Proceedings, 1876. No. 1-7. 8vo. The Society. 



Christiania : — Kongelige Norske Frederiks Universitet. Aarsberetning 

 for Aaret 1875. 8a'0. 1876. Universitatsprogram (Windrosen des 

 siidlichen Norwegens, von C. de Seue). 4to. 1876. Etudes sur les 

 mouvements de lAtmosphere, par C. M. Guldberg et H. Mohn. 

 4 to. 1876. De Skandinaviske og Arktiske Amphipoder, beskrevne 

 a£ Axel Boeck. Andet Hefte. 4to. 1876. Norges Flora, af A. 

 Blytt. Del III. 8vo. 1876. Le Boj^aume de Norvege et le peuple 

 Norvegien, par 0. J. Broch. 8vo. 1876. Enumeratio Insectorum 

 Norvegicorum, Auctore H. Siebke. fasc. 3. 8vo. 1876. De Yig- 

 tigste Ddtryk for Begreberne Herre og Fyrste i de semitiske Sprog, 

 af E. Blix. 8vo. 1876. Eussisk Sproglsere til praktisk Behov, af 

 I-Tans Blom. 8vo. 1876. Paul Christian Hoist's Efterladte 



