Lewis self-binding insulator

THE LEWIS SELF-BINDING INSULATOR.

In his article on the construction of lines for electric circuits, Mr. Thomas D. Lockwood, on page 89 of the March number of this journal, referring to the Lewis self-binding insulator, states that the conception of forming the outside screw in a direction opposite to the internal screw, in order to provide for the simultaneous attachment of the insulator to the line wire and the pin, is due to Frank L. Pope. This statement although technically correct, inasmuch as the device was patented to Mr. Pope on December 25th 1883, in justice to Mr. Lewis, requires an explanation. The invention was original with Mr. Pope, but after the issue of his patent, he for the first time learned that Mr. Lewis had at an earlier date conceived the same invention, and had embodied it in insulators manufactured under his supervision in England. While this circumstance does not of course impair the validity of Mr. Pope's patent, yet there can be no question that Mr. Lewis was a prior and independent inventor of the same device, and it is a matter of simple justice that he should have due credit therefor. In preparing his article, Mr. Lockwood of course had no access to other sources of information than those afforded by the records of the United States Patent Office.