Granite insulator made from Maine granite

[Newspaper]

Publication: The Lima News

Lima, OH, United States
vol. 3, no. 276, p. 5, col. 2


ELECTRICAL NOTES

Granite is not usually considered to be an insulator, but one of the electrical journals reports that insulators are made as follows: Maine granite is crushed and molded into form and molded at 3,000 degrees Fahrenheit. It resists all but hydrofluoric acid, and dots not crush at a lower pressure than 14,500 pounds per square inch, and gives a tensile strength of 480 pounds per square inch; 56,600 volts were required to pierce one-quarter of an inch of this material in the shape of cup insulators.

--

Keywords:Reconstructed Granite Company
Researcher notes: 
Supplemental information: Patent: 664,470
Researcher:Elton Gish
Date completed:August 1, 2007 by: Elton Gish;