The Woolrich Electrical Generator, now in
Thinktank, Birmingham Science Museum
Thinktank, Birmingham (formerly known as simply Thinktank) is a science museum in Birmingham, England. Opened in 2001, it is part of Birmingham Museums Trust and is located within the Millennium Point (Birmingham), Millennium Point complex on ...
, England, is the earliest
electrical generator
In electricity generation, a generator, also called an ''electric generator'', ''electrical generator'', and ''electromagnetic generator'' is an electromechanical device that converts mechanical energy to electrical energy for use in an extern ...
used in an industrial process. Built in February 1844 at the Magneto Works of Thomas Prime and Son, Birmingham, to a design by John Stephen Woolrich (1820–1850), it was used by the firm of
Elkingtons for commercial
electroplating
Electroplating, also known as electrochemical deposition or electrodeposition, is a process for producing a metal coating on a solid substrate through the redox, reduction of cations of that metal by means of a direct current, direct electric cur ...
.
Plaque
The generator stood for some time in the chapel of
Aston Hall, accompanied by a plaque bearing the following inscription:
Construction
The generator in its surviving form consists of eight axial bobbins with a magnetic field applied by four iron horseshoe magnets. The rectangular, wood frame measures tall, wide, and long. The generator was fitted with a
commutator
In mathematics, the commutator gives an indication of the extent to which a certain binary operation fails to be commutative. There are different definitions used in group theory and ring theory.
Group theory
The commutator of two elements, ...
, as electroplating requires direct current.
John Stephen Woolrich
The generator's designer, John Stephen Woolrich, was born in
Lichfield
Lichfield () is a city status in the United Kingdom, cathedral city and Civil parishes in England, civil parish in Staffordshire, England. Lichfield is situated south-east of the county town of Stafford, north-east of Walsall, north-west of ...
, England in late 1820. The second son of John Woolrich (c.1791–1843) and his wife Mary Woolrich (formerly Egginton),
[Baptismal register, ]St Mary's Church, Lichfield
St Mary's Church is a city centre church in Lichfield, Staffordshire England located on the south side of the market square. A church is reputed to have been on the present site since at least 1150 but the current building dates from 1870 and is ...
he was baptised at
St Mary's Church, Lichfield
St Mary's Church is a city centre church in Lichfield, Staffordshire England located on the south side of the market square. A church is reputed to have been on the present site since at least 1150 but the current building dates from 1870 and is ...
on 6 November 1820.
In August 1842 he was granted patent number 9431 for the use of a magneto-electrical machine (instead of
batteries) in electroplating, and the use of gold sulphite and silver sulphite as electrolytes. He offered to sell the rights to Elkingtons for the enormous sum of £15,000; they declined, and after some heated correspondence eventually, in May 1845, agreed to pay Woolrich £100 initially and then £400 annually for the rest of the term of the patent.
Woolrich later relicensed the patent himself to use in his own Magneto-Plating and Gilding Works in Great Charles Street, Birmingham,
[Post Office Directory of Birmingham, 1845] and in 1849 was listed as a "chemist & magneto-plater & gilder", residing at 12 James Street, just off
St Paul's Square in the
Jewellery Quarter.
[Post Office Directory of Birmingham, 1849]
He died at the age of 29 in early 1850, and was buried at
St Bartholomew's Church, Edgbaston on 4 March 1850.
[Burial register, St Bartholomew's Church, Edgbaston]
The elder John Woolrich is listed in the
United Kingdom Census 1841 as a "Chemist", and at the time of his death on 20 April 1843 was a lecturer in chemistry at the
Royal School of Medicine and Surgery in Birmingham. He had a particular interest in
electrochemistry
Electrochemistry is the branch of physical chemistry concerned with the relationship between Electric potential, electrical potential difference and identifiable chemical change. These reactions involve Electron, electrons moving via an electronic ...
, and in February 1819 wrote a letter entitled ''On Galvanic Shocks'' to the
Annals of Philosophy, pointing out an error in the editor
Thomas Thomson's book ''System of Chemistry''. He was granted a number of patents for chemical processes, including one in 1836 for an improved method of producing "carbonate of baryta" (
barium carbonate
Barium carbonate is the inorganic compound with the formula BaCO3. Like most alkaline earth metal carbonates, it is a white salt that is poorly soluble in water. It occurs as the mineral known as witherite. In a commercial sense, it is one of ...
) and another in 1839 for producing "
carbonate of lead, commonly called white lead".
See also
*
Dynamo
"Dynamo Electric Machine" (end view, partly section, )
A dynamo is an electrical generator that creates direct current using a commutator. Dynamos employed electromagnets for self-starting by using residual magnetic field left in the iron cores ...
*
Electromagnetic induction
Electromagnetic or magnetic induction is the production of an electromotive force, electromotive force (emf) across an electrical conductor in a changing magnetic field.
Michael Faraday is generally credited with the discovery of induction in 1 ...
*
Faraday's law of induction
References
{{Thinktank, Birmingham
Electrical generators
Collection of Thinktank, Birmingham
1844 in England
1844 in science