214 Aftion of Mercury on the Human "Body. [Book VI. 



then placed on the glafs fo as to prefs out dill more of 

 the quickfilver, and in a little time the tin foil, thus 

 united to the quickfilver, adheres fo firmly to the glafs 

 that the weights may be removed without any danger 

 of its falling off. About two ounces of quickfilver are 

 ufed in covering three fquare feet of glafs. 



In order to make mercury capable of acting on the 

 animal body, it is neceffary that it fhould undergo fome 

 preparation ; for its particles muft be very minutely 

 divided before they can enter the vefTels. Thus, if 

 we apply quickfilver to a capillary tube, the attrac- 

 tion of its particles for each other is fo ftrong that they 

 will not rife in it ; but minute divifion is not the only 

 circumftance neceffary to its activity, for Ethiop's mi- 

 neral and cinnabar taken into the body have very little 

 if any effect. Oxygenation feems to be the mod ef- 

 fential circumftance ; for in whatever way this is ef- 

 fected the mercury becomes very active *. 



Mercury, in paffing through the body, is reduced 

 to the metallic ftate, and, exuding through the pores, 

 fometimes attaches itfelf to the gold of watches, 

 rings, fleeve-buttons, or ear-rings, and renders them 

 white. 



* Does not the effefl of fulphur, in diminiming the activity 

 of mercurial preparations, depend on its fuperior attraction for 

 oxygen, by which it has a tendency to reduce the mercury to the 

 metallic ftate ? 



