112 OF ANIMAL IIKAT. 



it is scarcely increased by the heat of summer, or dimi- 

 nished by the cold of winter, but found sometimes even 

 to increase on immersion in cold water,* demonstrate 

 that the action of the minute vessels Varies according 

 to the temperature of the medium in which we are 

 placed '. so that, when exposed to a low temperature 

 (by which their tone is probably augmented) more oxy- 

 gen is exchanged for carbon and more heat evolved, 

 while in a high and debilitating temperature this ex- 

 change is diminished and less heat evolved, f 



171. The corium, which covers the body, and the 

 internal surface of the alimentary canal, eminently con- 

 tribute, if we are not much mistaken, to regulate our 

 temperature. For both these organs are supplied with 

 an immense number of blood-vessels, being analogous in 

 this respect to the lungs, and are so intimately con- 

 nected with the lungs by means of sympathy,^, as in 

 some degree to perform a part, and occasionally the 

 whole, of some of their functions in their room. This 

 is exemplified in adults labouring under nearly total 

 consumption, or other violent affections, of the lungs, 

 and nevertheless, existing for a length of time almost 

 without respiration. § 



* G. Pickcl, Experimenta Physico-Medica de EUctricitate et Colore ani- 

 malt. Wirceb. 1788. 8vo. p. 91 sq. 



t C. Fcrd. Becker, De Effectibus caloris et frigoris extemi in c. h. Gott. 

 1802. 4to. ; and Wni. Fr. Baur, On the tame subject. IB. EOD. (BOTH 

 honoured with the royal prize.) Mich. Skjcldcrup, Ditsert. tit tent vim 

 frigorit incitantem. Hafn. 1803. 8ro. 



X J. Chr. Fr. Goescken, (Pros. Ph. Fr. Meckel) Pulmonum cum Cute com- 

 virrcium. Hal. 1789. 8ro. But especially J. D. Brandis, Pathologic. 

 llaml). 1808. p. JJlfi »q. 



§ Consult, for instance, Tacconi, Covimcnt. Inttit. Bontniens. Vol. vi. p. 74. 



