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. XXIX. How to burn Silver under the Muffle.

[Section. 1] BƲRNING of Silver which principally is used in lower Saxony) requireth a singular and better Diligence than the Common silver burning, and also parti∣cular Tests and Muffles: The Tests you must make thus: Let the prepared Hoops be of Iron, of the bigness as you intend to burn a great or small piece of silver, they must be high of a hand square, but at the top a little wider than at the Bottom, in one of them put in the prepared Test-Ashes, and fill it to the top, still beating down gently (with a broad Hammer) the Ashes about the Brim; and so fur∣ther and further till you have beaten down all the Ashes that are left, or are too much upon the Test, stroak them off with an Iron, and then overturn the Rings and test alike upon a little Ashes, which is to be laid under; then take them with your hand out of the test, till it is half empty, and make the Ashes small again with your hands, then press the test full again with a heap beating it down also with the Hammer, as is before directed, and the rest of the Ashes also stroak off with an Iron, then turn the test again, and make the Ashes smooth with the Ball, then the test is prepared: Now the tests after this manner pre∣pared are much better and stronger than they which are beaten into the tests.

[Section. 2] Concerning the Muffles which pertain to this Silver-burning, they are to be made over little round sticks af∣ter the bigness of the upper part of the test, and are to be cut out in the like form with the tests; and other

pertaining Instruments which the Sculpture following will shew.

If now you will burn Silver, then put the Test with the Ring between four square burnt Stones in Sand or Ashes, as deep that the Sand may be even with the test above, in an Oven for it prepared, in which several tests may be put together, and such Wind-Ovens must have alwayes one Wind-hole, which may drive two Ovens, especially in such places wherein many pieces of Silver come together, and once in one day are to be burnt.

Afterwards put the Muffle on the test, which is made after its bigness, and a burnt stone on the top, that nothing may fall upon the Silver, put coals up∣on and under the Muffle, and about and upon the test, and when the test is grown warm then put in the beaten silver, and let it begin to work, but if you would have it soon melted, then you may blow it with Hand∣bellows, through the Mouth-hole under the Muffle, and then it quickly goeth, and when it is melted take away the Coals again, and let it go also under ths Muffle, stir it once or thrice with the Iron, as you have done in the other, then it will go upon the test, under the Muffle, all off: (just as the Silvers upon the Coppels.) With this burning of Silver both great and small pieces may be burnt, as with the Bellows, and without loss or any great damage upon the Content.

[Section. 3] After this manner, I have seen at Goslar in the Work∣house (when it was kept) upon one Test on one piece near one Hundred mark of Silver burning: If now you will (while the Silver goeth) take out with an Iron one or two provings (as is done in the Silver-burning before) you may do it (and it is not to be despised) but who in this ART is conversant, the same needeth not so many provings, but he knoweth it upon sight, when it hath enough.

[Section. 4] Now when the Silver under the Muffle is burnt clear and begins to stay, one may let water run upon it in a Copper Channel and cool it, then with strong Tongs take it out and purify it from the Ashes, (as is above∣said) then the Silver is burnt.

[Section. 5] The Tests may be kept together, because they are not without Silver, the same in some Mine-works the Work-men use to take to themselves, but in some they belong to the Republique: They may be made at any time to profit, and the Silver that is in them may be melted out, as may be seen in the following Sculpture, and is thus

[illustration]

Deciphered.

• 1. The Oven in which the Silver is to be burnt.
• 2. The inside of that Oven.
• 3. The Wind-holes of that Oven which drives the fire upwards into the Work.
• 4. The Test that is set into it.
• 5. The Iron Mould or Ring into which the Tests are to be put.
• 6. The form of the Iron∣ring.
• 7. The Ring fill'd with ashes for making a Test.
• 8. A round Muffle.
• 9. A Ball and Hammer for making of Tests.
• 10. A person that breaketh the burnt Silver.
• 11. Another person standing on the back-side of the Oven who takes Care for the burning of the silver.
• 12. A Vessel of water into which the burnt silver is to be cast.
• 13. Bellows and Instruments belonging to the Oven.

[illustration]

[Section. 1] Sculpture X.

Notes

• Tests to be made with with Iron rings.
• The Muffles for Silver burning.
• A clean sil∣ver burning
• Tests to be kept.