Download or read book Mineralogia Cornubiensis written by William Pryce and published by Рипол Классик. This book was released on 1778 with total page 399 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Collection of Scarce and Valuable Treatises Upon Metals Mines and Minerals written by Alvaro Alonso Barba and published by Theclassics.Us. This book was released on 2013-09 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt: This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1740 edition. Excerpt: ... call by the Name of Devil's Dirt; then there is no Way but to let all cool; and then to dig it out, and with more Lead to melt it again in a Pot, and then to let it cool, and then to break the Pot, and to beat off the Cinder with an Hammer, till you come to the malleable Metal, and you may be assured that no Royal Metal will stay in the Cinder, but sink down into the Lead, through an Attractive Virtue betwixt them. chap. lxvii. Wherein is /hewed the Operations of Silver. as for the melting thereof, when it is found in the Mine of Lead, theOperation is taught in the Chapter of Lead; but if it be found by itself, or mix'd with Gold without Lead, as many times it cometh to pass, then it is to be beaten to Powder, and mix'd with Sandiver, and Saltpetre, without any Filings of Iron, and Ib melted down like the Lead Oar; only the Fire must be somewhat stronger. Then it is to be melted with four times as much Lead, whereof you know the Goodness; and so to be refined, as before- is declared. Hot But whereas sometimes this Oar is so strongly mixed with Sparre, and stony Substances, that it cannot be separated therefrom, by any common Manner of Work used by the Refiners, then this Course is to be taken with it: First, beat it into small Powder, then wash away with Water the greatest part of the Terrestreity and Filth; then dry the Powder, and use it in this Manner. First, melt four Ounces of Lead, and when it is melted, put it to four Ounces of Quicksilver, made hot in another Melting pot; but let the Lead be almost cold before you put it to the Quicksilver;, but yet it must be done whilst the Lead is liquid. This done, cast it into an Iron Morter, set it warm before upon Embers, and it will be like Pap; then presently with a Pestel, labour...
