Page:The Art of Distillation, 1651.djvu/27

Book.1.Of the Art of Diſtillation. 3
which happens not in a Furnace of another figure, as four ſquare or triangular, for the corners diſperſe and ſeparate the force of the fire. Their magnitude muſt be ſuch as ſhall be fit for the receiving of the veſſel; their thickneſs ſo great as neceſſity ſhall ſeem to require; only thus much obſerve, that if they be made of forged Iron or Copper, they muſt be coated within ſide, eſpecially if you intend to uſe them for a ſtrong fire. They muſt be made with two bottomes diſtinguiſht as it were into two forges, the one below which may receive the aſhes, the other above to contain the fire. The bottom of this upper muſt either be an Iron grate, or elſe an Iron plate perforated with many holes, that ſo the aſhes may the more eaſily fall down into the bottom, which otherwiſe would put out the fire. Yet ſome Furnaces have three partitions, as the Furnace for Reverberation, and the Regiſter Furnace. In the firſt and loweſt the aſhes are received. In the ſecond the fire is put, and in the third of the Furnace for Reverberation the matter which is to be reverberated. This third ought to have a ſemicircular Cover, that ſo the heat may be reflected upon the contained matter. The bottom of the third and uppermoſt partition of the Regiſter Furnace muſt be either a plate of Iron, or a ſmooth ſtone perforated with holeſ, having ſtopples of ſtones fitted thereunto, which you may take out or put in, as you would have the heat increaſed or decreaſed. In the top or upper part of all theſe Furnaces where it ſhall ſeem moſt fit, there muſt be two or three holes made, that by them the ſmoak may more freely paſs out, & the air let in to make the fire burn the ſtronger if need require, or elſe which are to be ſhut with ſtopples made fit to them. The mouths of the forementioned partitions muſt have ſhutterſ, juſt like an Ovens-mouth, with which you may ſhut them cloſe, or leave them open if you would have the fire burn ſtronger. But in defect of a Furnace, or fit matter to make one, we may uſe a Kettle or a Pot ſet upon a Trefoot, as we ſhall ſhow when we come to give you a deſcription of the Furnace and Veſſels. The truth is, a good Artiſt will make any ſhift, yea and in half a dayes time make a Furnace or ſomething equivalent to it for any operations.

B 2CHAP.