Publication: Electrical Review
New York, NY, United States
Gilbert's Patent Shackle Ball
At present, when improved insulation is required at terminal poles, the usual custom is to terminate the wires on insulators of the ordinary pattern. This system, whilst electrically right, is sometimes mechanically imperfect, as there is great danger of the arm splitting and breaking; and, moreover, the insulator gets pulled over from its vertical position and looks unsightly.
It may be mentioned that since the introduction of these balls on the Highland Railway in England 2 1/2 years ago, the improvement in the insulation and the working of the wires is most-satisfactory, and therefore it is the intention to employ them to a much larger extent, so that in a little time the old and leaky double shackles will not exist.
Figs. 2, 3 and 4 show different ways in which the shackle balls may be introduced with advantage.
By adopting the arrangement shown by Fig. 1, Mr. Gilbert claims that, for an intermediate station, the cost would be much less than the ordinary Bright's shackle, whilst the superiority of the insulation would be most marked, there being three distinct breaks for the current in place of two. — London Electrical Review.