FEVERS. 607 



continued fevers. Those especially in use are, the Vitriolic 

 and Vegetable, and on many accounts we prefer the latter. 

 " It appears to me, that these refrigerants act very directly upon 

 the arterial system, diminishing its activity, and thus the heat 

 of the body also. The first and best known refrigerants are 

 acid substances generally. Their sedative operation is indeed 

 not easily explained, and I do not think it at all necessary to 

 attempt any explanation, but their power is universally acknow- 

 ledged by physicians, and they are generally used in haemorr- 

 hagies and phlegmasise, where the heat of the system is in- 

 creased in consequence either of increased reaction, or of particu- 

 lar changes in the state of the blood, in which case their effects 

 are still more evident. 



" I must, however, go still farther, and observe, that the acids 

 have by experience been found the most powerful quenchers 

 of thirst, which, indeed, occasions an especial appetite for acid 

 drinks. They diminish the heat of the mouth and fauces, occasion 

 some stimulus to the salivary and common secretions, and hence 

 are useful in taking off both the heat and the dryness upon 

 which thirst depends, and in obviating that clamminess of the 

 mouth which so frequently arises in fever. Their operation 

 extends still farther, to the stomach and intestines, where putrid 

 matters are liable to abound : indeed we know nothing more 

 immediately or strongly powerful in obviating that putrescency 

 than the use of acids. They might even be supposed to exert 

 their antiseptic power in the mass of blood as well as in the in- 

 testinal canal ; but I doubt this antiseptic power, considering 

 the small quantity in which they are taken, and their very gen- 

 eral diffusion throughout the body. Acids have another power, 

 however, in common with all saline substances, they are deter- 

 mined towards the several watery secretions, the perspiration 

 and urine, and it is obvious that in this way they may be of 

 considerable utility in fevers. 



" I suppose, upon good grounds, that all these effects may be 

 obtained by every kind of acid which is pure, and not combined 

 with any other substance. Of the fossil acids, the vitriolic is 

 now almost only employed ; and I know no good objection 

 against the nitric and muriatic acids. 



" The vegetable acids, however, may be employed, perhaps, 

 more properly and effectually than any of these fossil acids. 



