Substances which, like an air gap, interfere with the flow of electricity are called non-conductors, or, more commonly, insulators. 伯莎M.克拉克.科学通论.
In 1883 no such fittings as fixture insulators were known. 弗兰克·刘易斯·戴尔.爱迪生的生平和发明.
The little glass-knob insulators made seductive targets for ignorant sportsmen. 弗兰克·刘易斯·戴尔.爱迪生的生平和发明.
The farthest western reach of the telegraph lines in 1847 was Pittsburg, with three-ply iron wire mounted on square glass insulators with a little wooden pentroof for protection. 弗兰克·刘易斯·戴尔.爱迪生的生平和发明.
The insulators were bottles set on nails driven into trees and short poles. 弗兰克·刘易斯·戴尔.爱迪生的生平和发明.