Ophthalmic electromagnet, United Kingdom, c. 1940

Ophthalmology

1935-1945

Electromagnet for extraction of metal from the eye, steel, brass and wood, probably British, c. 1940

Cased electromagnet

Telecommunications

Electro-magnet, in glass case

Electromagnet

Electricity and Magnetism

Electromagnet, Electromagnet

Electromagnet used by James Jo

Scientific Instruments & Research

Electromagnet used by James Joule.

Superconducting Electromagnet, 1990

Electricity and Magnetism

1985-1995

Superconducting Electromagnet with support assembly, made by Cryogenic Consultants Ltd, 231 The Vale, London W3 7QS, England, c. 1990.

Small superconducting electromagnet

Electricity and Magnetism

1965

Small superconducting electromagnet, made by Oxford Instruments Ltd. in 1965

Horseshoe electromagnet, probably home-made

Science Teaching

1900-1980

Horseshoe electromagnet, probably home-made

Horseshoe-shaped electromagnet used by James Joule

Scientific Instruments & Research

Horseshoe-shaped electromagnet used by James Joule, c.1840. This electromagnet was used by the scientist James Joule for experiments about energy. Joule was a Salford resident and the son of a brewer. He was taught by the famous scientist John Dalton. Joule's experiments in 1845 led him to an new understanding of energy conversion.

Electromagnet for a crane, by Witton Kramer

Lifting & Mechanical Handling

Electromagnet for a crane, by Witton Kramer

Large superconducting electromagnet

Electricity and Magnetism

1963-1969

Large superconducting electromagnet, made at the Central Electricity Research Laboratories, between 1963-1969

Superconducting electromagnet

Electricity and Magnetism

1989-1990

Superconducting electromagnet, prototype of the magnet used in medical magnetic resonance imaging machines, made by Oxford Magnet Technology Limited, Wharf Road, Eynsham, Witney, Oxon, OX18 1BP, England, 1989-1990.

Large electromagnet by Ducretet

Electricity and Magnetism

1879-1883

Large electromagnet by Ducretet, formerly the property of Spottiswoode

Part of Electromagnet

Scientific Instruments & Research

1855

Electromagnet used by James Joule, c.1855.

Part of Electromagnet

Scientific Instruments & Research

1860

Electromagnet used by James Joule, c.1860.

Replica of James Joule's Electromagnet

Scientific Instruments & Research

Replica of an electromagnet used by James Joule, the original of which was used in 1843 to demonstrate the heating effect of an electric current. Horizontal glass cylinder wound with cotton fabric. Armature of metal strip bound together and wound with cotton-covered copper wire.

Electromagnet used by James Joule in about 1839 for experiments on the attracting power of magnets

Scientific Instruments & Research

Electromagnet used by James Joule in about 1839 for experiments on the attracting power of magnets. Iron bar is wound with '88 yards of covered copper wire 1/16" diameter.' One of a pair of magnets used to test the law that 'the attractive force of two electromagnets is directly proportional to the square of the electric force to which the iron is exposed', i.e. M (attraction) = E squared (electric current) x W squared (length of wire). Results showed that as the length of the bar is increased, so the power of attraction increases.

Electromagnet Core

Scientific Instruments & Research

1855-1865

Electromagnet core used by James Joule, c.1860. Cylinder of concentric layers of soft iron insulated by cotton tape.

Electromagnet core

Scientific Instruments & Research

1835-1845

Electromagnet core made by James Joule for electromagnetic engine. Used to experiment on the shape of wire most suited to Joule's electromagnetic engine. The practical advantage of the solid magnet outweighed the wire magnet. Described in Joule's 1839 paper 'On the use of Electro-magnets made of iron Wire for the Electromagnetic Engine'

Electromagnet made by James Joule for experiments on lifting power

Scientific Instruments & Research

1840

Electromagnet made by James Joule for experiments on lifting power, c. 1840. One of a number of electromagnets constructed to investigate how much work could be extracted, Experiments carried out at Salford brewery. Long cylindrical piece of iron divided in two longitudinally; one half wound with cotton-covered copper wire, other half wound only in centre. Both halves have eyelet drews along their length.

Electromagnet originally used for magnetising compass needles

Electricity and Magnetism

Electromagnet originally used for magnetising compass needles

Electromagnet Core

Scientific Instruments & Research

1855-1865

Electromagnet core used by James Joule, c.1860. Made of concentric layers of soft iron insulated by cotton tape.

Newport type N38 electromagnet

Electricity and Magnetism

1981

Newport type N38 electromagnet

Ferranti,electromagnet

Electricity and Magnetism

Ferranti,electromagnet

Part of Electromagnet

Scientific Instruments & Research

1855

Electromagnet used by James Joule, c.1855.

Electro-magnet horseshoe form

Childrens Gallery

Electro-magnet horseshoe form

Electromagnet Type E

Electricity and Magnetism

1960-1979

Electromagnet type E serial no. 7156/6 by Newport Instruments, Newport Pagnell, England

Electromagnet used by James Joule

Scientific Instruments & Research

Electromagnet used by James Joule, c.1840.

Part of Electromagnet

Scientific Instruments & Research

1855

Part of electromagnet used by James Joule, c.1855.

Electromagnet used by James Joule

Scientific Instruments & Research

Electromagnet used by James Joule, c.1840.

Electromagnet Core

Scientific Instruments & Research

1839

Electromagnet core used by James Joule, c. 1839 to measure electromagnetic attraction. Made up of 16 square sections of iron wires and covered in strips of cotton. Deduced that the attractive force of two electromagnets for one another is directly proportional to the square of the electric force to which the iron is exposed; or if E is electric current, w the length of wire and M magnetic attraction, M=E squared x W squared. Originally 'wrapped with 22 yards of covered wire' now missing.