ABSTRACT
A variety of apparatus has been devised with the object not only of carrying the current through the liquid, but preventing local action or divergence of the current, with the risk of intermixture of the oxygen and hydrogen. An apparatus was devised in which, by means of automatic reversing gear, the air could be alternately introduced into the retorts under slight pressure, and after absorption of the oxygen and escape of the nitrogen, the oxygen could be pumped off by reducing the pressure below atmospheric, but without altering the temperature of the retorts and their contents. The use of the oxyacetylene blowpipe flame for welding and for cutting through metal plates has recently extended so much as to lead to a greatly increased consumption of oxygen independently of hydrogen. “By using the well-known rectification process followed in the manufacture of alcohol, the nitrogen can be completely separated from the oxygen.
