Add to Lightbox Add to Lightbox Buy Image Buy Image

This image is protected by copyright law. Please contact us for advice on our licensing terms, before reproducing it for commercial purposes.

To save a small version of this image for mock-up or research purposes, right click (or control click on Macintosh) and Save Picture As...

Fox dip and intensity apparatus, c 1840.

Detail of jewel bearings. Dip circles are used to measure the angle between the direction of the earth’s magnetic field and the horizontal at any point on the earth’s surface. A magnetic needle on a horizontal axis lays horizontally only at the magnetic equator, where the attraction to the poles is equally balanced. Elsewhere, the needle will dip to an angle which depends on the distance from the nearest magnetic pole. At the north and south magnetic poles the needle dips vertically. Dip circles were frequently taken on scientific expeditions from the 18th century onwards. This apparatus demonstrates the variation in design introduced by R W Fox in 1834, to allow for use on a moving ship and the measurement of both magnetic force and dip. Made by W George.

Image No. 10284432 | This is a Rights Managed image.

Inventory No.: 1908-0097
Source No.: 1908-0097

Credit © Science Museum / Science & Society Picture Library -- All rights reserved.
Search for related items:
To search for related items, choose from the following related keywords. To search multiple keywords, select multiple checkboxes and click Search Selected. To search for a single keyword, click the keyword itself.
Show items that have: