Publication: The Telegraphic Journal and Electrical Review
THE FISKE-MOTT INSULATOR.
IN this insulator, which we noticed in the Electrical Review of New York, the amount of contact surface between the wire and the insulator is decreased, the groove in which the line and binding wires are placed being simply corrugated. With this pattern the insulation is said to be about ten times as great as that given by the ordinary kinds, whatever this latter expression may mean in America. It is also claimed that in this insulator there is no place for the lodgment of water or dirt, and that it is kept quite clean by the action of the wind and rain. We believe the article is manufactured by the Chicago Insulator Company.
We may remark that practical experience has shown most conclusively that very little, if any, increase in the insulation of a wire is obtained by such contrivances as the above. Theoretically speaking, two wires, one laid upon and at right angles to the other, should not be in electrical contact, since the contact takes place at a mathematical point, but actually the contact may be of practically zero resistance. The same is the case with insulators, for actually, the surfaces in contact, although apparently very small, are quite sufficient to enable the current to pass freely and thence to spread all over the surface of the porcelain and thus get to earth. To obtain high insulation in an insulator, length with small diameter is necessary.