620 SUMMARY OF CURRENT RESEARCHES RELATING TO 



exposed to temperatures of from zero to —80° F. for eight hours, 

 curdled, and showed the well-known Bacterium lactis ; and so far as 

 could be observed, freezing did not delay the process after the flasks 

 were kept at a temperature of about 50° F. Similar results were 

 obtained with ale, meat-juice, vegetable infusions, &c. 



It is probable that the micro-organisms were frozen solid. One 

 cannot suppose that in these circumstances any of the phenomena 

 of life take place; the mechanism is simply arrested, and vital 

 changes resume their course, when the condition of a suitable tem- 

 perature is restored. These conditions led the authors to examine 

 whether any of the vital phenomena of higher animals might be re- 

 tained at such low temperatures. They ascertained that a live frog 

 may be frozen through quite solid in about half-an-hour at a tem- 

 perature of — 20° to — 30° F. On thawing slowly, in two instances 

 the animal completely recovered. After longer exposure the animals 

 did not recover. In two cases frogs were kept in an atmosphere of 

 — 100° F. for twenty minutes, and although they did not revive, yet, 

 after thawing out, their muscles still responded feebly to electrical 

 stimulation. One experiment was performed on a warm-blooded 

 animal — a rabbit. The cold-blooded frog became as hard as a stone 

 in from ten to twenty minutes, but the rabbit produced in itself so 

 much heat as enabled it to remain soft and comparatively warm 

 during an hour's exposure to — 100° F. Still its production of heat 

 was unequal to make good the loss, and every instant it was losing 

 ground, until, at the end of the hour, its bodily temperature had 

 fallen about 56° F. below the normal, but was still 143° F. above the 

 surrounding temperature. When taken out the animal was coma- 

 tose, and reflex action was abolished. Placed in a warm room, its 

 temperature rose rapidly, and the rabbit completely recovered. 



The observations are of great value and highly suggestive. Those 

 upon the rabbit indicate that death from cold is preceded by loss of 

 consciousness, owing to the early suppression of the activity of the 

 grey matter of the encephalon. This confirms the belief that death 

 by freezing is comparatively painless. The viability of microbes at 

 low temperatures has also been demonstrated by Pictet and Yung,* 

 who found that various bacilli can survive —70° C. for 109 hours. 

 After such exposure. Bacillus anthracis retained its virulence when 

 injected into a living animal. 



" We cannot refrain from asking. Are not frozen micro-organisms 

 the means of disseminating life through the universe ? An affirma- 

 tive answer is at least a better hypothesis than the assumption of 

 spontaneous generation to account for the origin of life on the earth. 

 May not life be coeval with energy ? May it not have always 

 existed ? " f 



Bell's ' Comparative Anatomy and Physiology.' J— In this manual 

 Professor F. Jeffrey Bell arranges the elementary facts of zoology by 



* See this Journal, iv. (1884) p. 432. 

 t Mr. C. S. Minot in Science, v. (1885) pp. 522-3. 



X Bell, P. J., ' Comparative Anatomy and Physiology,' S.'iS pp. and 229 fi^-s 

 8vo, Gassell and Co., London, 1885. ■' oj, it 



