This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1912 Excerpt: ...are not actually ruined by this restoration it is extremely difficult to say whether they were made before the invention of plating on both sides of the ingot or not. The ultimate decision as to the age and intrinsic value has to depend, more...