Mining historian Kerby Jackson introduces us to a classic mining publication on the evaluation and examination of mines and prospects by C.H. Aaron. First published in 1881, it has been unavailable for over a century and sheds important light on the leaching of gold and silver ores with the Plattner and Kiss processes. Note: This edition is a perfect facsimile of the original edition and is not set in a modern typeface. As such, some type characters and images might suffer from slight imperfections or minor shadows in the page background.