Brooks insulators used exclusively on the Pennsylvania railroad

Brooks Insulators, Siemens Galvanometers,

Cables, &c.

THE new advertisement of Mr. DAVID BROOKS of his Patent Insulators, and of Siemens' Universal Galvanometers, Resistance Coils, Submarine Cables, etc., will be found worthy the attention of all who are engaged in telegraphy.

We have so often expressed our opinion of the superiority of the Patent Insulator invented and manufactured by Mr. BROOKS, that we can add little to what has already appeared in THE TELEGRAPHER in regard to them. They have fully vindicated their claims to being the best and only perfectly reliable insulator in general use for telegraphic purposes. It is adopted exclusively for the extensive lines of the Philadelphia Railroad Company, and on many other lines, and, in addition to its acknowledged merits as an insulator, experience has shown that, taking into account the expenses of maintenance, it is also the most economical.

SIEMENS' Universal Galvanometer, for the measurement of resistances, has an established recommendation in this country, as well as abroad, for excellence, simplicity and correctness. Mr. BROOKS is the agent in this country of Messrs. SIEMENS BROTHERS, and furnishes also their submarine cables, and cables for river crossings.