25 AUGUST 1894, Page 23

Handbook of Gad-Mining. Illustrated. By Henry Louis. (Mac- millan.)—This is

an exhaustive guide to the theory and practice of gold-milling, with the necessary adjuncts of amalgamation, calcination, cyaniclation, and assaying. The most important part, however, is the actual milling, the machinery of which is expen- sive, and subject to great wear and tear. Economy, of course, has a groat field in the other processes, particularly in the treat- ment of "tailings." The great question of the day for gold-reef companies, is to reduce the expenses which preclude profit, unless an unusually rich reef turns up. Mining people will find dis- cussion of stamps and frames and the particular curve of the "cam" practical and exhaustive.