Page:The Art of Distillation, 1651.djvu/26

2 and Calcination, which are of dry ubtances, unles I hall by the way make ue of either in relation to the perfecting of any kind of Ditillation. Now becaue all, or mol of thee Ditillations are to bee performed by heat, it will be neceary to undertand how many degrees of heat there are, and which are convenient for every operation, and they are principally four. The firt is only a warmth, as is that of Hore dung of the Sun, of warm water, and the vapour thereof, which kind of heat erves for putrefaction, and digetion. 2. The econd is of eething water, and the vapour thereof, as alo of ahes, and erves to ditill thoe things which are ubtile, and moit, as alo for the rectifying of any Spirit or Oil. 3. The third is of and and filings of Iron, which erves to ditill things ubtle, and dry, or gros and moit. 4. The fourth is of a naked fire, cloe, open, or with a blat which erves to ditill Metals and Minerals, and hard gummie things, as Amber; &c. I doe not ay erves only to ditill thee, for many of the former Ditillations are performed by this heat, as the ditilling of Spirits and Oils, &c. in a Copper till over a naked fire; but thee may be ditilled by the two former degrees of heat; but Minerals and uch like cannot but by this fourth degree alone.

Of the matter and form of Furnaces He matter of Furnaces is various, for they may be made either of brick and clay, or clay alone with whites of Eggs, hair,and filings of Iron, (and of thee if the clay be fat are made the bet, and mot durable Furnaces) or of Iron, or Copper cat or forged. The forms alo of Furnaces are various. The fittet form for Ditillation is round; for o the heat of the fire being carryed up equally diffueth it elf every way, which