Star Porcelain Company wiring knob

Porcelain Insulator

The latest type of confining insulator designed to get rid of the tie wire is shown herewith. The insulator is made in two parts by the Star Porcelain Company, of Trenton, N. J. As shown in the engraving, the upper part of the insulator is made to straddle the wire and the projection of the lower portion, on which the wire rests, is so shaped that when the upper part is fastened in place, the wire is curved slightly and thus resists any slipping or pulling action. The wire is thereby not only safely insulated, but securely fastened. A screw passing through one side of the top part, and also through the lower part, serves to hold the insulator in place. Between the screw and the wire is a wall of porcelain, so that contact between them is not possible. The insulator is said to meet all the requirements of the fire underwriters.

Porcelain Insulator.