114 THE INFLUENCE OF INANIMATE SURROUNDINGS. 



the same, and is not poisoned by the introduction into its cir- 

 culation of the dead corpuscles from its frozen legs. From 

 Pouchet's point of view it might be answered that the amount 

 of poison supplied by the freezing of the legs was insufficient to 

 do permanent injury to the frog after they were thawed. But 

 the question is not one of any present moment. 



At any rate, the results of Horvath's experiments, which 

 agree with Pouchet's, as to the deadly effects of freezing, make 

 the various observations as to the revival by thawing of frozen 

 animals in the highest degree improbable. Horvath showed 

 that a frog, or a portion of a frog, infallibly died when frozen in 

 a temperature of the surrounding medium (water or quicksilver) 

 of 5 or more below zero 0. ; whereas nerves, muscles, and hearts, 

 after being reduced to a temperature of from to 4 below zero C. 

 or even actually frozen, are said to be capable of renewed activity 

 when thawed again. From this we may infer that the essential 

 part of muscular fibre or nerve-tissue, on which their functional 

 activity depends, is not brought to its freezing-point even when 

 reduced to a temperature of 5 centigrade. But we cannot 

 extend this conclusion to whole animals, for we do not know 

 whether other parts of the body, as, for instance, the blood or 

 gland-cells, might not freeze at a still higher temperature and die 

 in consequence, and then the whole animal would undoubtedly 

 be killed. However, exact estimates of the internal heat of 

 animals thus hard frozen are not at hand ; it was concluded 

 at once from their stiffness that they were frozen through 

 and through, without the least consideration of the fact that 

 the freezing-point of the different juices found in the body may 

 vary greatly, and that consequently, even in apparently hard- 

 frozen animals, those parts may not be actually frozen on whose 

 properties their resuscitation by thawing essentially depends. 

 Horvath's experiments ought to have been repeated, in a com- 

 prehensive way, on uninjured animals before a positive opinion 

 could be formed on earlier observations. 38 



Meanwhile these as well as Horvath's experiments show 

 that there are animals which can bear to be frozen up, and even to 

 be in part actually frozen. From this a latitude in their power 

 cf resistance to variations of temperature is presumable, which 



