Publication: The Electrical Engineer
New York, NY, United States
The accompanying cuts, Figs. 1 to 5, illustrate a type of insulator comparatively unknown in the United States, though used in other countries. They are manufactured by Johnson & Phillips, of London. These devices were designed for the purpose of obtaining the highest insulation by preventing surface leakage.
An insulating fluid which, it is stated, will not support a film of dust or moisture, fills a recess, well protected from the weather, in the porcelain body of the insulator. In this way a clean and highly insulating fluid surface is interposed between the line and earth. The insulators are found to be especially efficient in rainy weather.
These insulators, which are made in numerous patterns of either porcelain or brownware, may be employed to advantage on coast lines, where the glass or porcelain quickly becomes coated with a conducting film of salt.
The insulation fluid is manufactured by Johnson & Phillips, London, under a secret process.
The fluid, it is claimed, does not freeze; it does not evaporate; and allows dust to sink to the bottom; it does not creep like paraffin or other mineral oils and lasts three or four years, even in the East Indian climate. One gallon of the insulation fluid suffices for about 20 of the smaller and 14 of the larger insulators. These insulators are handled by the Electrical Supply Company, of Chicago.