Note 528 — Chapter XIII · SHOCK PROJECTILES
Reading edition
90.5 per cent. copper and 9.5 per cent. tin; copper at 2s. 34d. per lb. (average, 1303-53); tin at 3.41d. per lb. (average, 1371-80). Mr. Rogers notices the rareness of copper, 1350-1400. Ib., i. 484; ii. 531. The bronze of an Egyptian mirror, cir. 1750 B.C., was found by M. Berthelot to consist of 91 per cent. copper and 9 per cent. tin.—Introd. Alchimistes Grecs, p. 221.