of Animals to secure Warmth. 505 



native inhabitants differed only about 1 or 2 from the ordi- 

 nary standard in England*. At very high temperatures, 

 however, there is a little more difference, as appears from the 

 ingenious experiments made by MM. Delaroche and Berger, 

 who exposed themselves to a heat of 228, sixteen degrees 

 above that of boiling water: they ascertained that, at such 

 very high temperatures, there is an increase of seven or eight 

 degrees of the centigrade thermometer j. The increase of 

 cold, on the contrary, does not appear to influence the tem- 

 perature of the body in a similar way, and hence we discover the 

 cause why great cold proves less injurious and fatal to animals 

 than might be a priori anticipated. White of Selborne, speak- 

 ing of gipsies, says, ' these sturdy savages seem to pride them- 

 selves in braving the severity of the winter, and in living 

 sub dlo the whole year round. Last September was as wet a 

 month as ever was known ; and yet, during these deluges, did 

 a young gipsy girl lie in the midst of one of our hop-gardens, 

 on the cold ground, with nothing over her but a piece of a 

 blanket extended on a few hazel-rods, bent hoop fashion, and 

 stuck in the earth at each end, in circumstances too trying for 

 a cow in the same condition : within this garden there was a 

 large hop-kiln, into the chambers of which she might have 

 retired, had she thought shelter an object worthy her atten- 

 tion J.' The half wild cats, mentioned above, were more 

 attentive to their comforts than this young gipsy ; since a 

 neighbouring kiln for drying corn was their favourite resort 

 when the fire was lit. 



The law by which animal temperature is thus maintained at 

 nearly the same degree on exposure to considerable heat or 

 cold, though it is not easy to reconcile it to any of the received 

 theories, supplies the only known reason why some of the 

 smaller and seemingly tender animals outlive the rigours of 

 our severest winters. The magpie (Pica caudata, RAY), 

 though rather a hardy bird, has been found having recourse to 

 what is often practised by smaller birds several of them hud- 

 dling together during the night to keep each other warm. A 

 gentleman of intelligence and veracity informs me that he once 



* Phil, Trans, for 1 814, p. 600. f Jour, de Physique, kxi. 289. 



J Nat. Hist, of Selborue, lett, 67. 



