Benefit of Porcelain Insulators Over Glass Known in Europe

AN ELECTRICIAN'S APPEAL TO PORCELAIN MANUFACTURERS

The subjoined appeal to porcelain manufacturers is from Mr. Francis W. Jones, the well-known electrical engineer and inventor, and now electrician of the Postal Telegraph Cable Co., of this city. What Mr. Jones says on the matter of insulators is not only important but true, and it does seem to us that American porcelain manufacturers should have no difficulty in meeting the demand. It should certainly be worth their while, as the insulators used by the Western Union and Postal companies alone must run up into millions, with a steady consumption every year:

To the Porcelain Manufacturers of America:

Up to the present time in this country, glass has been chiefly used for the insulation of telegraph lines. In Europe, however, porcelain is the prevailing material and presents three or four times more resistance to the leakage of current than glass. The great cost of importation under a high tariff, coupled with a lack of knowledge of the advantages gained in Europe by the use of porcelain, are undoubtedly the reasons why glass has been so long adhered to in America, notwithstanding that great loss of business occurs during rains and fogs by the electricity leaking down the poles, rendering the wires inoperative. The insulating properties of porcelain depend on its quality. It requires a good smooth surface, must be perfectly vitrified throughout so as to be homogeneous, impervious to moisture and free from flaws; the glaze must be good. If such an article can be produced in this country, it sooner or later undoubtedly will replace all the glass in use, even should quite a difference in price exist in favor of glass. It would be an advantage if the shape could be made to conform to the present double-petticoat glass, but it may be thought best to adopt the English Post Office pattern. To convince you of the soundness of my views, see F. L. Pope's 1891 edition of "Modern Practice of the Telegraph," page 115. Also Preece & Sivewright's last edition on "Telegraph," page 267. Mr. Preece is electrician of the British postal lines. You will feel convinced, I am sure, that a field is open for your careful consideration and action. I shall be pleased to hear from you further on this (to me) important subject.

F. W. Jones, Electrician.

Postal Telegraph-Cable Company,

New York, Jan. 5, 1892