Elements of the art of assaying metals. [electronic resource] : In two parts. The first containing the theory, the second the practice of the said Art. The Whole Deduced from the true Properties and Nature of Fossils; confirmed by the most accurate and unquestionable Experiments, explained in a natural Order, and with the utmost Clearness. By John Andrew Cramer, M.D. Translated from the Latin. Illustrated with copper plates. To which are added, several notes and observations not in the Original, particularly Useful to the English Reader. With an appendix, containing a List of the chief Authors that have been published in English upon Minerals and Metals.