288 DISEASES SECT. XXXII. 3. 3, 



lation of blood in the lungs, occafioned by the preflure as well 

 as by the -oldnefs of the water. This is not a fatisfaftory ac- 

 count of this curious phenomenon, fince at this time the 

 whole circulation is lefs, as appears from ihe fmallnefs of the 

 pulfe and colclnefs of the breath ; which {hew that lefs blood 

 pafTes through the lungs in a given time ; the fame laborious 

 breathing immediately occurs when the palenefs of the fkin is 

 produced by fear, where no external cold or preflure are applied. 



The minute veflels of the bronchia, through which the blood 

 pafles from the arterial to the venal fyltem, and which corref- 

 pond with the cutaneous capillaries, have frequently been ex- 

 pofed to cold air, and become quiefcent along with thofe of the 

 Ikin ; and hence their motions are fo aflbciated together, that 

 when one is affected either with quiefcence or exertion, the 

 other fympathizes with it, according to the laws of irritative 

 ailbciation. See Sect- XXVII. I. on haemorrhages. 



Befides the quiefcence of the minute veffcls of the lungs, 

 there are many other fyftems of veflels which become torpid 

 from their irritative afibciations with thofe of the Ikin, as the 

 abforbents of the bladder and inteftines ; whence an evacution 

 of pale urine occurs, when the naked fkin is expofed only to 

 the coldnefs of the atmofphere ; and iprinkling the naked body 

 with cold water is known to remove even pertinacious confti- 

 pation of the bowels. From the quiefcence of fuch extenfive 

 iyftems of veflels as the glands and capillaries of the fkin, and 

 the minute veflels of the lungs, with their various abforbent fe- 

 ries of vefiels, a great accumulation of fenforial powers is occa- 

 fioned ; part of which is again expended in the increafed ex- 

 ertion of all thefe veflels, with an univerfal glow of heat in con- 

 fequence of this exertion, and the remainder of it adds vigour 

 to both the vital and voluntary exertions of the whole day. 



If the activity of the fubcutaneous veflels, and of thofe with 

 which their actions are aflbciated, was too great before cold im- 

 merfion, as in the hot days of fummer, and by that means the 

 fenforial power was previoufly diminifhed, we fee the caufe 

 why the cold bath gives fuch prefent (trength ; namely, by {top- 

 ping the unncceflary activity of the iubcutaneous veflels, and 

 thus preventing the too great exhauftion of fenforial power ; 

 which, in metaphorical language, has been called bracing the 

 fyftem : which is, however, a mechanical term, only applicable 

 to drums, or mufical ftrings : as on the contrary the word re- 

 laxation, when applied to living animal bodies, can only mean 

 too fmall a quantity of ftimulus, or too fmall a quantity of 

 fenforial power ; as explained in Sect. XII. i. 



3. This experiment of cold bathing prefents us with a fimplc 



fever- fit > ; 



