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steady rut of the Society。 After serving an apprenticeship in his
native town； he was sent to Coalbrookdale on a mission of business；
where he became acquainted with the Darby family； and shortly after
married Hannah； the daughter of Abraham the second。 He then entered
upon the conduct of the iron and coal works at Ketley and Horsehay；
where he resided for six years； removing to Coalbrookdale in 1763； to
take charge of the works there； on the death of his father…in…law。
By the exertions and enterprise of the Darbys； the Coalbrookdale
Works had become greatly enlarged； giving remunerative employment to
a large and increasing population。 The firm had extended their
operations far beyond the boundaries of the Dale： they had
established foundries at London； Bristol； and Liverpool； and agencies
at Newcastle and Truro for the disposal of steam…engines and other
iron machinery used in the deep mines of those districts。 Watt had
not yet perfected his steam…engine； but there was a considerable
demand for pumping…engines of Newcomen's construction； many of which
were made at the Coalbrookdale Works。 The increasing demand for iron
gave an impetus to coal…mining； which in its turn stimulated
inventors in their improvement of the power of the steam…engine； for
the coal could not be worked quickly and advantageously unless the
pits could be kept clear of water。 Thus one invention stimulates
another； and when the steam…engine had been perfected by Watt； and
enabled powerful…blowing apparatus to be worked by its agency； we
shall find that the production of iron by means of pit…coal being
rendered cheap and expeditious； soon became enormously increased。
We are informed that it was while Richard Reynolds had charge of the
Coalbrookdale works that a further important improvement was effected
in the manufacture of iron by pit…coal。 Up to this time the
conversion of crude or cast iron into malleable or bar iron had been
effected entirely by means of charcoal。 The process was carried on in
a fire called a finery； somewhat like that of a smith's forge； the
iron being exposed to the blast of powerful bellows； and in constant
contact with the fuel。 In the first process of fusing the ironstone；
coal had been used for some time with increasing success； but the
question arose； whether coal might not also be used with effect in
the second or refining stage。 Two of the foremen； named Cranege；
suggested to Mr。 Reynolds that this might be performed in what is
called a reverberatory furnace；*
＇footnote。。。
Reverberatory； so called because the flame or current of heated gases
from the fuel is caused to be reverberated or reflected down upon the
substance under operation before passing into the chimney。 It is
curious that Rovenson； in his Treatise of Metallica of 1613；
describes a reverberatory furnace in which iron was to be smelted by
pit…coal； though it does not appear that he succeeded in perfecting
his invention。 Dr。 Percy； in his excellent work on Metallurgy； thus
describes a reverberatory furnace： 〃It consists essentially of
three partsa fireplace at one end； a stack or chimney at the other；
and a bed between both on which the matter is heated。 The fireplace
is separated from the bed by a low partition wall called the
fire…bridge； and both are covered by an arched roof which rises from
the end wall of the fireplace and gradually dips toward the furthest
end of the bed connected with the stack。 On one or both sides of the
bed； or at the end near the stack； may be openings through which the
ore spread over the surface of the bed may be stirred about and
exposed to the action of the air。 The matter is heated in such a
furnace by flame； and is kept from contact with the solid fuel。 The
flame in its course from the fireplace to the stack is reflected
downwards or REVERBERATED on the matter beneath； whence the name
REVERBERATORY furnace。〃
。。。＇
in which the iron should not mix with the coal； but be heated solely
by the flame。 Mr。 Reynolds greatly doubted the feasibility of the
operation； but he authorized the Cranege； to make an experiment of
their process； the result of which will be found described in the
following extract of a letter from Mr。 Reynolds to Mr。 Thomas Goldney
of Bristol； dated 〃Coalbrookdale； 25th April； 1766 〃：
。。。。 〃I come now to what I think a matter of very great consequence。
It is some time since Thos。 Cranege； who works at Bridgenorth Forge；
and his brother George； of the Dale； spoke to me about a notion they
had conceived of making bar iron without wood charcoal。 I told them；
consistent with the notion I had adopted in common with all others I
had conversed with； that I thought it impossible； because the
vegetable salts in the charcoal being an alkali acted as an absorbent
to the sulphur of the iron； which occasions the red…short quality of
the iron； and pit coal abounding with sulphur would increase it。 This
specious answer； which would probably have appeared conclusive to
most； and which indeed was what I really thought； was not so to them。
They replied that from the observations they had made； and repeated
conversations together； they were both firmly of opinion that the
alteration from the quality of pig iron into that of bar iron was
effected merely by heat； and if I would give them leave； they would
make a trial some day。 I consented； but； I confess； without any great
expectation of their success； and so the matter rested some weeks；
when it happening that some repairs had to be done at Bridgenorth；
Thomas came up to the Dale； and； with his brother； made a trial in
Thos。 Tilly's air…furnace with such success as I thought would
justify the erection of a small air…furnace at the Forge for the more
perfectly ascertaining the merit of the invention。 This was
accordingly done； and a trial of it has been made this week； and the
success has surpassed the most sanguine expectations。 The iron put
into the furnace was old Bushes； which thou knowest are always made
of hard iron； and the iron drawn out is the toughest I ever saw。 A
bar 1 1/4 inch square； when broke； appears to have very little cold
short in it。 I look upon it as one of the most important discoveries
ever made； and take the liberty of recommending thee and earnestly
requesting thou wouldst take out a patent for it immediately。。。。 The
specification of the invention will be comprised in a few words； as
it will only set forth that a reverberatory furnace being built of a
proper construction； the pig or cast iron is put into it； and without
the addition of anything else than common raw pit coal； is converted
into good malleable iron； and； being taken red…hot from the
reverberatory furnace to the forge hammer； is drawn out into bars of
various shapes and sizes； according to the will of the workmen。〃
Mr。 Reynolds's advice was implicitly followed。 A patent was secured
in the name of the brothers Cranege； dated the 17th June； 1766