Page:Electrical Engineering Volume 1.djvu/24

 the conductivity of the different substances, beginning with silver, which is the best conductor known.

A general idea of these values may be obtained from the fact that water has 6,754 million times greater resistance than copper.

2219. An electric charge will be induced in a conductor when that conductor is brought into the vicinity of an electrified body. This effect is termed electrostatic induction, and the range of space in which it can take place is an electrostatic field.

2220. If the conductor A B, Fig. 904, is supported from contact with the earth by insulators, and is then brought into the electrostatic field of the conductor C, but not touching C, which is electrified with a positive charge, then:

1. A charge will be produced on A B, as is shown by the pith-balls spreading apart.