122 Poifonous Nature of Arfenic. [Book VI. 



Sulphur unites readily with arfenic into a compound 

 more fufible than the arfenic itfelf. Orpiment is a 

 combination of arfenic and fulphur, of a yellow co- 

 lour. It is found naturally in the earth, generally of 

 an irregular form, and compofed of Ihining flexible 

 laminse. Its fpecific gravity, according to Kirwan, 

 is 5,315, who alfo aflerts that it contains one- tenth 

 part of its weight of fulphur. The fame author men- 

 tions, that realgar, or the red combination of arfenic 

 and fulphur, contains fixteen parts of fulphur in the 

 hundred, and is of the fpecific gravity of 3,225. 

 Chaptal, however, obferves that the difference between 

 realgar and orpiment does not confift in the propor- 

 tions of fulphur, nothing more being neceffary in order 

 to convert orpiment into realgar, .than expofure to a 

 ftrong heat. The violent action of arfenic on the 

 animal machine is much abated by combination with 

 fulphur. Common white ar'enic has fomctimes been 

 fuccefsfully ufed in dofes of one-twelfth or one-fix- 

 teenth of a grain. Received, however, in any confi- 

 derable quantity into the body, it produces drynefs of 

 the mouth, heat in the throat, excruciating pains in 

 the bowels, attended fometimes with vomiting of 

 blood, cold fweats, &c. On direction, the bowels 

 are found inflated an'd corroded. Many black and 

 livid fpots appear on the ftomach and fmall inteftincs, 

 fometimes gangrenous. But thefe figns are not 

 altogether to be depended on. Some of the arfenic is 

 frequently found, and may be eafily diitinguifhed. 

 The powder is heavy, and eafily feparates from the 

 lighter contents of the bowels, by waftiing with water; 

 the arfenic always falling to the bottom. A very little 

 of this is fufficient to give the fmell of garlic, and tinge 

 copper white, if heat is applied to it. 



It v/as formerly ufual to- give mucilaginous drinks, 

 or milk or miid oils, to perfons poifoned by arfenic. 



But 



