Rensselaer Republican, Volume 21, Number 33, Rensselaer, Jasper County, 18 April 1889 — Not Generally Known. [ARTICLE]

Not Generally Known.

Seamless boiler tubes are now made from solid ingots of metal by a process that twists and stretches the fibers, and is said to make a tube much stronger than the ordinary ones. Frenchmen qf science have produced artificial emeralds by fusing silica, alumna and glucina with traces of oxide of chromium acid molydate of at a temperature of 600° to 700° for fifteen days. Vr .