FEVERS. 639 



" From this historical detail, it will appear plainly that from 

 both the ancients and the moderns, we have enough of facts to 

 consider cold applied to the surface of the body as a remedy of 

 some importance, and that it may have place wherever the use 

 of cold water as a drink is admissible. 



" The facts, however, are not so well ascertained in continued 

 fevers as they are in smallpox, where the effects of cold air are 

 very apparent. In continued fever the cold not only moderates 

 reaction, but also acts as a tonic. There is wanted an experiment 

 with the thermometer, to show first the increase of heat in an 

 eruptive fever, and, secondly, the degree of diminution after 

 exposure to cold. 



" When .the tonic power of cold is wanted, ought its applica- 

 tion to be transient ? A typhus patient has been relieved by 

 washing him with cold water, but the same person continuing 

 immersed would probably have been injured." 



CCXI. The medicines which have been employed in fevers, as 

 tonics, are various. If the Saccharum Saturni has been found 

 useful, it is probably as a tonic rather than as a refrigerant ; and 

 the Ens Veneris, or other preparations of iron which have been 

 employed, can act as tonics only. The preparations of copper, 

 from their effects in epilepsy, are presumed to possess a tonic 

 power ; but whether their use in fevers be founded upon their 

 tonic or their emetic powers, may be uncertain. The use of 

 arsenic and of alum, in intermittent fevers, seems manifestly 

 to depend upon their tonic power. And, upon the whole, there 

 may occur cases of continued fevers, which may be cured by 

 tonics taken from the fossil kingdom : but the use of these has 

 been rare, as well as the effects uncertain ; and physicians have 

 employed, more commonly, the vegetable tonics. 



CCXII. A great variety of these has been employed in the 

 cure of intermittent fevers ; but how many of them may be em- 

 ployed in continued fevers, or in what circumstances of these 

 fevers, is not well ascertained ; and I shall now only consider 

 the question with respect to the most celebrated of these tonics, 

 the Peruvian bark. 



CCXIII. This bark has been commonly considered as a 

 specific, or as a remedy of which the operation was not under- 



