Publication: Electrical World
New York, NY, United States
The D. M. Steward Manufacturing Company, of Chattanooga, Tenn., is crowded with orders for its lava insulators, although it has a capacity for turning out nearly 50,000 of these per week. One of the large electrical companies is now ordering its special form of insulators in lots of 50,000, and many of the manufacturing companies are having all work of this done in lava. The Steward Company have just completed a trolley line insulator, which is said to be the strongest ever made. Recent tests made of the resistance of the Steward lava are said to have shown that it has a resistance of 50 megaohms. It was also tested by heating nearly to incandescence and then plunging into cold water. It stood this remarkable test, it is said without developing the slightest perceptible crack, and the Steward Company is now preparing tubes of this material in various lengths and diameters, which are said to be cheaper than rubber or fibre.