Fleta minor the laws of art and nature, in knowing, judging, assaying, fining, refining and inlarging the bodies of confin'd metals : in two parts : the first contains assays of Lazarus Erckern, chief prover, or assay-master general of the empire of Germany, in V. books, orinally written by him in the Teutonick language and now translated into English ; the second contains essays on metallick words, as a dictionary to many pleasing discourses, by Sir John Pettus ... ; illustrated with 44 sculptures.

CHAP. XXI. How to make Ovens to Distill Aqua Fort.

[Section. 1] EVERY one useth to prepare the Ovens to the distilling of Aqua Fort. according to his pleasure: But there is one Form much better, and more profitable than the other (as I have seen and used many my self▪ for I finde, That the Ovens called Athanors, which, as in the following Sculpture is [Section. 2] properly delineated, are the best to be used to distil Aqua fort. and they are to be formed thus, Make a Steeple in square or round four Els high, and below in it lay an Iron Grate, under vvhich must be a Wind-hole, according to the demonstration in the next Sculpture: and then make again on both sides of the steeple, in the same wideness, according to the height of the Juggs or Glass-bottles round or square Ovens, in which the Glas∣ses or Juggs may stand: Put also below in the steeple or tower, Iron-Grates, so that it may have wind-holes below: in such By-Ovens must be left holes from the Tower, that the heat (as you shall hear) may come out of it, and if they are about a large span wide, and four fingers and a span high, then are they wide and high enough: only observe, That when you do set up the high Tower, you do not make it two thick near to the holes, but rather narrower▪ that the fire or heat may go the better into the By-Ovens, then cause to such holes, through which the heat doth pass, fit Instruments of Potters-work, with which you may govern the fire as you please.

[Section. 3] Some cause such Instruments or Registers to be made of strong Iron, but they are not so good as the earthen, for, if the Iron one become hot and glowing, then they give likewise great heat, and if they are drawn before the fire, then they cannot well be managed or govern'd by it, and there is also danger therein.

[Section. 4] Further, you must also have to every By-Oven (in vvhich you set the Jugs or Glass-Bottles) covers made of Earth or Potters-clay, which must be cut out also, that they close just on the neck of the Jug or Glass-Bot∣tle, and that the Ovens may be shut very close, and leave Air-holes through it (being called Registers) and have Pins of Wood which go in very close to govern the Fire by it, as you may see in the eighth figure of the next Sculpture. Likewise upon the Tower a cover is to be set, which must be so large that it may cover all the upper holes of the Tower; and so is the Oven or Atha∣nor prepared to distil the Aqua fort. But how it should be governed with the Wind-holes followeth hereafter in the next Sculpture

[illustration]

Deciphered.

• 1. The Athanor.
• 2. The Mouth-hole over the Grate.
• 3. The Mouth-hole under the Grate.
• 4. The Grates in the By-Ovens.
• 5. The By-Ovens.
• 6. Instruments to open or shut the By-Ovens Mouth.
• 7. A Cover for the By-Oven.
• 8. The Pins for the Registers or Wind-holes.
• 9. A Semicircle piece of Wood by which the Athanor is to be made round.
• 10. The Cover for the Athanor.
• 11. The person that tends them.
• 12. A dish of Metals to be used.

[illustration]

Sculpture XXI.

Notes

• Athanor.