ebonite

plural ebonites

1. countableuncountableThe relatively hard product of vulcanizing natural rubber with sulfur.

   1 more example

   BRITISH CONSTRUCTION OF TELEGRAPHIC APPARATUS. R. S. Culley states that small insulators, formed of good porcelain, are the best, although, on several accounts, ebonite is recommended. Dirt and moisture are the principal things to be guarded against, but not all; for many mischievous boys, who would not take the trouble to break an unpretending black cap, can not resist the temptation of throwing at a large white one. Insects, especially spiders, are a source of peculiar annoyance. In the high roads of Ireland they are very troublesome, and in India, however large an insulator may be, an insect of the proper size is always ready to inhabit it. With respect to the construction of a line of telegraph the author states that it is preferable to use suspended rather than buried wires, because of the liability of gutta-percha and india-rubber to deteriorate underground, the expense of repairing faults, and the retardation of signals in consequence of the greater inductive capacity of wires so laid. On the other hand, gutta-percha is indestructible in sea-water, which is not, however, the case with india-rubber.

   1875, “Electricity, Light, Heat, Sound”, in Alfred E. Beach, editor, The Science Record for 1875: A Compendium of Scientific Progress and Discovery During the Past Year (Science Record), volume 4, Munn and Company, page 239

   Synonyms: vulcanite, hard rubber