From Tungate's manuscript:
Just as developments in extraction of iron and copper were interlinked, through the work
of Derby, who had been involved with the Bristol Brass Company in 1702, innovations
introduced in the brass industry by the Champion family and others may have inspired
parallel improvements in forming steel by Benjamin Huntsman.227 Although William
Champion of Bristol took out a patent for making spelter (zinc) in 1738, brass was
generally made by the cementation process where metallic copper was heated with
charcoal plus calamine (ZnCO3) in enclosed containers. Boulton was in correspondence
with Champion and wrote in his notebook: 'Champion says he has a patent for making
brass in spelter pots; that the same furnace serves either for spelter or brass as you
want.'228 He then suggested his own method with a research program to find out at what
225 Cort set up a rolling mill in Fontley, Hampshire where he developed ideas patented in 1783 for the grooved rolling
process and in 1784 for his balling or pudding furnace which made standardised bars of metal. The puddling process
involves stirring the molten iron in a series of stages to allow the separation of impurities. First the iron was melted in a
'refinery'. The iron was poured into a trough and the slag run of, thus reducing silicon content. This produced a brittle
white or 'finers' metal which was re-melted and stirred in the puddling furnace. A resultant puddled ball of iron was
extracted from the furnace using a rabbling bar and hammered, or 'shingled', and then rolled in a rolling mill to form
bars which would be broken up and faggotted. Wrought iron which had been faggoted twice was referred to as 'Best';
if faggoted again it would become 'Best Best', then 'Treble best' etc. Chris Evans and Göran Ryden (eds.) (2005) The
Industrial Revolution in Iron: The Impact of British Coal Technology in Nineteenth Century Europe Ashgate, Aldershot
p14.
226 MS 3782-12-29-32 Henry Cort () to MB (Soho) 3 Jun. 1784; MS 3782-12-29-31 Joseph Black (Edinburgh) to Mr.
Cort (Stourbridge, Worcestershire) 28 May 1784.
227 T.S. Ashton (1924) Iron and Steel in the Industrial Revolution; K.C. Barraclough (1984) Steel Making before
Bessemer Volume 1: Blister steel pp 60-69.
228 Boulton wrote: '3 furnaces in one set and require one man and assistant. Each furnace has 9 pots; 8 in a circle and
1 in centre; at each melting they make 2 cwt of brass in 24 hours Pots may last ½ a year or less. The bottom of the
furnice on which the Pots stand is called a siege and is made of cast iron with some holes in it to give air to the
furnace. 20 tons per furnace per year. So will need 10 furnaces at Birmingham New Co. to make 200 tons pa but as 3 in
set will need 12 furnaces. Each furnace is charge with 48lb brass and 72lb of calamine divided into 9 pots with
charcoal sufficient to fill & phlogisticate them. One furnace burns 12 bushels or 9 cwt of coals in 24 hours; 1s 6d per
day in coals for each bushel.' MS 3782-12-108-27 1780-1790 Boulton's General notebook.
61
temperature zinc, bath metal, brass and copper melt.229 This research was in conjunction
with setting up a Brass Company in Birmingham.
230 There was no large scale
manufacture using home produced zinc until 1781.231 The cementation method was
brought to perfection at the Cheadle Brass Company. A similar process, where carbon
was added to iron bars in an enclosed container, was used for steel.
Steel
Steel, an alloy of iron, was considered a semi-precious metal in the eighteenth century,
made in small batches, and used to make decorative objects such as buttons and buckles,
with methods of production more often associated with gold and silver. It was also
important for making functional objects such as specialist tools and dies.232 Steel can
have a wide variety of differing mechanical properties, due the different formation of its
alloys but this was only understood in a very empirical way in the mid-eighteenth
century. Steel was made at first by 'accident,' as a by-product in the bloomery. To a
trained eye it was possible to select the bits of iron that had been 'steeled' due to carbon
being added. 233 Blister steel had been made in Britain by the cementation process, on a
small scale, since the early decades of the seventeenth century, by heating iron bars with
229 This was done by pouring molten samples into cold water and calculating the increase of heat. MS 3782-12-108-27
1780-1790 Boulton's General Notebook.
230 Williams wrote in June 1781: 'I was told yesterday your new Metal Company at Birmingham differed among
themselves insomuch that their dissolution was apprehended, that their dissension had arisen from the peremptory
demand to have old Champion as chief manager of all their intended works.' MS 3782 12-73 Item 20 Thomas
Williams (London) to MB [Soho] Jun 1781.
231 J. Morton (1983) Thomas Bolton and Sons Limited 1783-1983
232 G. Ryden (2007) Steel in Britain in the age of Enlightenment A report on the colloquium held with the support of the
British Academy, Cardiff 7-8 December 2007.
233 Catalan steel, also known as 'german', acier or natural steel, was formed when iron ore containing a low silica and
high manganese content was selected, and more charcoal and a rapid air flow were used. T.S. Ashton (1924) Iron and
Steel in the Industrial Revolution p 87; The Südergebirge, a hilly region to the south of the Ruhr basin, was the source
of much of the high-grade german steel, imported into Britain before the rise of domestically produced cementation
steel, and for much that was imported for specialist uses long after. This area was also the point of origin for the steel
refining techniques that were transplanted to the North-East of England at the turn of the eighteenth century. H.L. Knau
(2007) Steel in Britain in the age of Enlightenment Colloquium held in Cardiff 7-8 December 2007.
John Lorenzo = Note in reference 230 Williams writes to Matthew Boulton about his new brass company in Birmingham. The Zn levels could really only have come from the Champion process and the dezincification process. This reference was recently found. Who made the RI Ship Medal? The metal source as I argued seems to reside with Boulton and Champion. See Hodder's write-up a the Notre Dame site. I believe Williams would replace Champion. But note the medal was thought to be produced around 1780. Only Boulton and Champion had the company, technology and the ability to produce this high level Zn brass. See the paper below and this page number:
(Page 61).Who struck the medal still is a mystery. Many argue it too crude for Boulton's hand but perhaps in 1780 it was not - in either case I was always convinced it was Boulton's brass that produced this medal in 1780 due to its elevated zinc and the fact Boulton and Champion were PARTNERS in business.
See reference 278 in this paper. It's probably the Birmingham Metal Company in 1780 that produced this high zinc brass for this medal (IMO) that some call a token.
http://etheses.bham.ac.uk/3202/9/Tu...inusvol2.pdfMATTHEW BOULTON
AND THE SOHO MINT:
COPPER TO CUSTOMER
by SUE TUNGATE
A thesis submitted to The University of Birmingham
for the degree of
DOCTOR OF PHILOSOPHY
JPL
Posted 02/07/2016 5:28 pm
