682 



ANIMAL HEAT. 



the solid and the fluid part. The more 

 the secretion eliminated abounds in solid parts 

 or matters formed at the cost of the solid 

 constituents of the blood, the more is the 

 blood impoverished in these elements the 

 more is its mass of globules diminished. 

 Absorption then begins, as in the preceding 

 case, to make up the quantity of circulating 

 fluid ; and if this faculty have only fluids to 

 work upon, it is evident that, as in the case of 

 bloodletting, the blood will become more serous 

 than before. The perspiration and the alvine 

 secretions act in this manner, and nature 

 makes use of these, especially of the former, 

 to temper the burning heat of paroxysms of 

 fever. Art but imitates nature in the treat- 

 ment of acute diseases ; she strives to procure 

 action of the skin, and especially action of 

 the bowels. The use of diaphoretics and pur- 

 gatives is therefore plainly borne out by the 

 principles which have been laid down. The 

 alvine secretions are those especially that carry 

 off the largest proportion of solid matters from 

 the blood, and which therefore, when excited, 

 prove the most permanently efficient in keep- 

 ing down the temperature of the body. There 

 is another important reason for preferring the 

 intestinal canal to the skin as the means, in 

 the generality of instances, of reducing tem- 

 perature in the treatment of disease, which 

 ought not to be lost sight of: this is, that 

 we can excite the intestinal evacuations to a 

 great extent without arousing the circulating 

 system in almost any degree ; very different 

 from what occurs when we attempt to unload 

 the vessels by the way of the cutaneous exha- 

 lants, in which it is generally impossible to 

 produce abundant diaphoresis without arous- 

 ing the heart and arteries to unwonted action 

 as a preliminary. Purgative medicines, there- 

 fore, next to the direct abstraction of blood, 

 are the most potent means of tempering the 

 heat of the body by modifying the consti- 

 tution of the blood. Nothing that influences 

 the economy can have an effect in one direc- 

 tion only. It were foreign to our purpose, 

 however, to enter upon any other than that 

 which bears immediately upon our subject. 



There is another natural process analogous 

 in its effects, which the preceding consider- 

 ations place in a new point of view. This 

 is the influence of diet and regimen. Low 

 diet does not act merely in preventing the ex- 

 citement which always follows the ingestion of 

 solid food ; it further alters the constitution of 

 the blood. This fluid, receiving a more scanty 

 supply of solid matters, continues nevertheless 

 to supply the natural secretions as before, and 

 consequently very speedily undergoes by this 

 alone a diminution in the proportion of its 

 globules, in the direct ratio of the duration of 

 the system of spare diet. Low diet is there- 

 fore a means which acts in the same way as 

 bloodletting and purging, with this difference 

 however, that it is slower in its operation, and 

 in the first instance less marked in its effects. 

 This, therefore, is the slowest and least efficaci- 

 ous of the immediate means of reducing tem- 

 perature when employed alone, although its 



conjunction is indispensable to the success of 

 any of trie others. 



Of all these means, one only is the proper 

 effect of art, namely, the application of cold ; 

 the others are processes of the same natura 

 medicatrir, and processes which we merely 

 imitate. These act directly in modifying the 

 constitution of the blood, and thus definitively 

 influence the nervous system. The other 

 exerts its influence directly on the nervous 

 system, in calming the excitement or violent 

 action which it has engendered in the sangui- 

 ferous system, and those that depend on it. 



The application of heat becomes necessary 

 in morbid states the reverse of those that 

 have just been discussed. The proper employ- 

 ment of this means depends especially on 

 two general principles bearing upon animal 

 heat, which we have considered above. 1st, 

 The one is, that the economy has the capacity 

 of bearing heat in the same proportion as 

 the function of respiration is extended. In 

 those cases in which this function is limited, 

 or, what comes to the same thing, where any part 

 that requires an accession of heat is indiffer- 

 ently supplied with arterial blood, it is neces- 

 sary to be extremely cautious in its applica- 

 tion. 2nd, The other, that the effects of ex- 

 ternal heat are not confined to the simple 

 interval during which it is applied, but remain 

 after it has been removed, and even increase 

 the faculty of producing heat. The applica- 

 tion of warmth is therefore not merely pallia- 

 tive or supplementary of lost heat; it has 

 further a directly remedial influence, which 

 may even be excited in excess. When the 

 lesion of the calorific faculty has been great, 

 without much or any organic lesion, other 

 means of greater force than those usually re- 

 sorted to by art, or employed by nature in 

 such circumstances, must be called in to assist. 

 Art has happily discovered what seems the 

 most effectual means of winding up the 

 nervous system, and enabling the calorific 

 faculty to be re-established in its normal con- 

 dition. This means is quinia, the first of 

 tonics. This powerful medicine is conse- 

 quently never administered in acute diseases 

 until all violence of action has ceased, and 

 the functions have resumed their habitual 

 rythm. We find that the action of this 

 medicine is exerted directly upon the nervous 

 system from this, that it seems to have no 

 effect on the secretions, or when it does in- 

 fluence these, we are convinced by the tri- 

 fling amount of the effect, that it is not through 

 them that the cure is accomplished. As it 

 acts during the intermission, by restoring the 

 normal production of heat, we have no reason 

 to expect the phenomena which characterize 

 the fit the shivering, &c. ; and then the vio- 

 lent reaction which we have in the hot stage 

 becomes useless, and in fact is no longer ob- 

 served. 



CONFIRMATION OF THE GENERAL RESULTS. 

 We have thus passed in review the principal 

 phenomena of animal heat, reducing or ap- 

 proximating these at all times to the most 



