A Peruvian chisel, analysed by M. Vauquelin, contained 0·94 copper to 0·06 tin. In other tools the proportion of the latter metal varied from two to four, six and even seven per cent. As a rule the people used only half the proper proportion of tin, which they called Chayantanka—a name suggesting the Old-World ‘Tanuk.’ Humboldt mentions a cutting tool found near Cuzco with ninety-four per cent. of copper and six of tin. Rivero (i. 201) notices in Peru brass (?) hammers and bellows-nozzles, axes, adzes, bill-hooks, and other tools, of bronze as well as copper. The Mexicans cast their tin ingots in T-shape. The Peruvians hardened copper also with silver for quarrying-tools and crow-bars. Velasco (ii. 70) tells us that when the Ynka Huasca was being led to prison by order of his brother, a woman secretly gave him a bar of metal, ‘silver with bronze, brass, or an alloy of silver, copper, and tin’ (Bollaert, p. 90); by means of this he cut through the jail wall during the night. Hutchison (ii. 330) mentions a buckler from Ipijapa in Ecuador, and Ewbank (p. 454) notices an old Peruvian bronze knife.[278] [Heading: _PROPORTIONS OF ALLOYS._] The admirable bronzes of China and Japan are well known in the English market, and Raphael Pumpelly,[279] who studied direct from the native workmen, has printed interesting notes on the ornamental alloys, or Mokume, applied to Swords and other articles. Damask-work is produced by soldering alternately thirty to forty sheets of rose-copper, silver, _shakdo_ (copper one to gold ten per cent.), and _gui shi bu ichi_ (silver and copper). The mass is then cut into deep patterns with the reamer. An alloy of silver (thirty to fifty per cent. of copper) produces the favourite tint, a rich grey colour, and this becomes a bluish black like niello by being boiled after polishing in a solution of sulphate of copper, alum, and verdigris. Dr. Percy (p. 340) describes the liquation of argentiferous copper in Japan.[280] We owe to Dr. George Pearson[281] sundry experiments in alloys, which first determined that the norm of the Old World and the best proportion for weapons and tools are one tin to nine copper. Fusing the metals, he found: 1 tin : 20 copper (5 per cent.) produces a dark-coloured bronze with the red fracture of the pure metal. 1 tin : 15 (6½ per cent.) gives a stronger alloy and obliterates the colour. 1 tin : 12, 9, 8, 7, 6, 5, 4, 3 gradually increases hardness and brittleness. 1 tin : 2 makes a mixture almost as brittle as glass. The following table[282] shows the alloys now in common use, and the purposes to which they are applied: