32 Influence of Atmospheric Temperature 



scarcely goes beyond the removal of the old and noxious errors 

 of close atmosphere, hot rooms, and thick clothing ; — doubtless 

 a very beneficial change, but not precluding the more direct 

 and extensive application of cold to the surfaces of the body.* 

 Whatever the theory of this action, the benefits gained are in- 

 contestible ; — familiar to all who have fairly employed it, and 

 well recognised by patients themselves. Almost may it be 

 taken as a rule, that wherever there is a hot and dry skin, cold 

 in one degree or other may safely and expediently be applied 

 to change its state. The benefit of simple abstraction of heat 

 is great in such cases ; and the fact is not sufficiently adverted 

 to, which I have often put to thermometrical test, of the ex- 

 tent to which this influence is diffused beyond the surface to 

 which the cold is immediately applied. There is no real risk 

 here to countervail the good gained. We are sedulous in pro- 

 viding for and varying the application of heat to the body ; 

 while, from one cause of alarm or another, little provision is 

 made for the opposite remedy, though not less capable of being 

 actively and beneficially employed. 



A point subordinate to this, which has had less notice than 

 its practical importance deserves, is the influence of cold or 

 hot air respectively, upon wounds or open surfaces. The 

 greater sensibility of parts so exposed, and the more direct ac- 

 tions on their vascular texture, make this condition a very im- 

 portant one. And accordingly we have much proof in private 

 practice — still more from the experience of hospitals and mili- 

 tary campaigns — of the eff^ects produced by heat and cold se- 

 verally, or by changes from one to the another. I have seen this 

 remarkably in the army hospitals in Portugal ; where in sum- 

 mer, the general rate of recovery from wounds was accelerated 

 or retarded, as the temperature became suddenly cooler, or 

 the reverse. It is singularly attested in the instance of the 

 wounded, left exposed on the field of battle. Though the better 

 understanding of ventilation has contributed towards this ob- 

 ject, yet might much more benefit be derived from the direct 



* I say mrfaces, because in fact cold acts reraedially on the lining of the 

 alimentary canal, as "^ell as on the outer skin ; is often as imperatively re- 

 quired by the sensations of the patient ; and not less sanctioned by the good 

 obtained. 



