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BOOK VII.
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The method of assaying ore used by mining people, differs from
smelting only by the small amount of material used. Inasmuch as, by smelting a small quantity, they learn whether the smelting of a large determining quantitative values, which is the fundamental object of the assayer's art, and
all their discussion is shrouded in an obscure cloak of gibberish and attempted mysticism. Nevertheless, therein lies the foundation of many cardinal assay methods, and even of chemistry itself. The first explicit records of assaying are the anonymous booklets published in German early
in the 16th Century under the title Probierbüchlein. Therein the art is disclosed well advanced toward maturity, so far as concerns gold and silver, with some notes on lead and copper. We refer the reader to Appendix Β for fuller discussion of these books, but we may repeat here that they are a collection of disconnected recipes lacking in arrangement, the items often repeated, and all apparently the inheritance of wisdom passed from father to son over many generations. It is obviously intended as a sort of reminder to those already skilled in the art, and would be hopeless to a novice. Apart from some notes in Biringuccio (Book in, Chaps, ι and 2) on assaying gold and silver, there is nothing else prior to De Re Metallica. Agricola was familiar with these works and includes their material in this chapter. The very great advance which his account represents can only be appreciated by comparison, but the exhaustive publication of other works is foreign to the purpose of these notes. Agricola introduces system into the arrangement of his materials, describes implements, and gives a hundred details which are wholly omitted from the previous works, all in a manner which would enable a beginner to learn the art. Furthermore, the assaying of lead, copper, tin, quicksilver, iron, and bismuth, is almost wholly new, together with the whole of the argument and explanations. We would call the attention of students of the history of chemistry to the general oversight of these early 16th Century attempts at analytical chemistry, for in them lie the foundations of that science. The statement sometimes made that Agricola was the first assayer, is false if for no other reason than that science does not develop with such strides at any one human hand. He can, however, fairly be accounted as the author of the first proper text-book upon assaying. Those familiar with the art will be astonished at the small progress made since his time, for in his pages appear most of the reagents and most of the critical operations in the dry analyses of gold, silver, lead, copper, tin, bismuth, quicksilver, and iron of to-day. Further, there will be recognised many of the " kinks " of the art used even yet, such as the method of granulation, duplicate assays, the " assay ton " method of weights, the use of test lead, the introduction of charges in leaf lead, and even the use of beer instead of water to damp bone-ash. The following table is given of the substances mentioned requiring some comment,
and the terms adopted in this book, with notes for convenience in reference. The German terms are either from Agricola's Glossary of De Re Metallica, his Interpretalio, or the German Translation. We have retained the original German spelling. The fifth column refers to the page where more ample notes are given :— |
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