Quicksilver. 169

lution muft be made nearly to boil, and continuedin that heat for three or four hours, now and dienfhaking the veffel,—towards the end making it boilgently, for a quarter of an hour. See more on thisfubject in Scheele's EJfays, and the Notes ofDr. Bed-does.

As it has been fuppofed by many to be a new in-vention of Mr. Scheele, and recommended by himas an eafy and cheap fubftitute for Calomel, it has"come pretty much into ufe; but the teftimonies,before the Committee, of its good effects, not beingconfonant with each other, the College chofe not toreceive it inftead of a medicine of fuch eftablifhedcharader as Calomel, and introduced this for futuretrial. It is given in dofes fimilar to thofe of Calomel.

HYDRARGYRUS NITRATUSRUBER.

Red nitrated Quicksilver.

Take of purified Quickfilver,

Nitrous Acid, of each one pound.

Muriatic Acid, one dram by weight.

Mix them in a glafs veffel, and diffolve th»Quickfilver in a fand-bath j then raife the

fire,