1820.] Scientific Intel/igence. 309 



sia. This stone has been lately analyzed by Stromeyer, and 

 found to be composed as follows : 



Silica 38-0574 



Magnesia 29-9306 



Alumina 3-4688 



Protoxide of iron 4-8959 



Oxide of manganese 1-1467 



Oxide of chromium 0-1298 



77-6292 



Iron 17-4896 



Nickel 1-3617 



Sulphur 2-6957 



98-7762 

 (Gilbert's Annalen, Ixiii. 451.) 



VI. Calomel. 



Corrosive sublimate was known to the Arabians, and is dis- 

 tinctly enough described by Avicenna, and, according to Berg- 

 man, by Abubeker-al-Rhasi, who preceded Avicenna by at least 

 a century ; but we have no evidence that calomel, or a/erciii-ius 

 diilcis, as it was formerly called, was known to the alchymists. 

 Crollius, in his Basilica Chymica, published in 1608, hints at it 

 as a most valuable preparation of mercury, but without giving 

 the least information about the method of preparing it. The 

 same year Joannes Beguin published a book in Paris, entitled 

 " Tyrocinium Chemicum," in which he described the whole 

 process of making calomel, and lie distinguished the preparation 

 by the name of Draco miticratits. This mercurial preparation 

 verv speedily acquired great celebrity, and came to be distin- 



fuished by the name o^ panchi/inagogiis qusrcitanwi, in honour of 

 oseph Du Chesne Domini de la Violette, a very famous French 

 chemist of those days, who published in 1615 a work, entitled 

 " Pharmacopcea Dogmaticorum Restituta." During the 18th 

 century, the term merciirius dnlcis came into general use to denote 

 this preparation of mercury, or sometimes it was called iiiercurius 

 subliniatus dnlcis ; but this mode of naming was blamed by 

 Neuman, because it was apt to occasion corrosive sublimate and 

 mercurius dulcis to be confounded together. The term calomelas 

 (which signifies beautiful black) was introduced by the French 

 chemists, and applied to mercurius dulcis, when several times 

 sublimed, which, in their opinion, added greatly to its virtue. 

 I do not know who the person was who first applied this term ; 

 but I think it must have been between the years 1730 and 1766. 

 I cannot find the term in any French book older than 1730, and 

 Spiehnann, whose Institutiones Chemiai were published in the 

 year 1766, gives us the term calo/uelas as new, and as not gene- 

 rally received by chemists. Bergman, whose paper On the 



