Note 49 — INTRODUCTION.
Clements R. (Clements Robert) Markham translation
Humboldt mentions a cutting-instrument found near Cuzco, which was composed of 0.94 parts of copper and 0.06 of tin. The latter metal is scarcely ever found in South America, but I believe there are traces of it in parts of Bolivia. In some of the instruments silica was substituted for tin.