Chapter V: METALLURGY.--How Gas Cylinders are Made.--The manufacture

of cylinders for highly compressed gases, a comparatively
new and growing industry.--6 illustrations.

Refining Silver Bullion.--The Gutzkow process in refining silver
bullion with sulphuric acid.--1 illustration.

The Treatment of Refractory Ores.--A new process for the extraction
of metal from refractory ore.--1 illustration.

Weldless Steel Chains.--An exhaustive examination of this curious
process, and very full illustrations.--43 illustrations.