Paper, 'On a new scale for tangent galvanometers' by W H [William Henry] Preece and H R Kempe

Description

Preece and Kempe write: 'Tangent galvanometers are much used for the exact quantitative measurement of currents of considerable strength, such as are measured in ampères, but they are not so generally used for the measurement of smaller currents in milliampères. This arises from a notion that they are not sensitive enough; although the most sensitive instrument in practice—Sir William Thomson's mirror galvanometer—is really a tangent instrument. The ordinary forms—Joule’s, Gaugain’s, or Helmholtz’s—are not very sensitive. Their constant is about three, that is, three amperes are required.'

Annotations in pencil and ink. Includes two diagrams relating to the galvanometer.

Subject: Physics / Scientific apparatus and instruments

Received 6 May 1886. Read 10 June 1886.

A version of this paper was published in volume 40 of the Proceedings of the Royal Society as 'On a new scale for tangent galvanometers'.

Reference number

PP/8/32

Earliest possible date

1886

Physical description

Ink and graphite pencil on paper

Page extent

12 pages

Format

Manuscript
Diagram