Industrial Biography: Iron Workers and Tool Makers

by Samuel Smiles

It appears from the 'Blast Furnace Memorandum Book' of Abraham Darby, which we have examined, that the make of iron at the Coalbrookdale foundry, in 1713, varied from five to ten tons a week. The principal articles cast were pots, kettles, and other "hollow ware," direct from the smelting-furnace; the rest of the metal was run into pigs. In course of time we find that other castings were turned out: a few grates, smoothing-irons, door-frames, weights, baking-plates, cart-bushes, iron pestles and mortars, and occasionally a tailor's goose. The trade gradually increased, until we find as many as 150 pots and kettles cast in a week.

The fuel used in the furnaces appears, from the Darby Memorandum-Book, to have been at first entirely charcoal; but the growing scarcity of wood seems to have gradually led to the use of coke, brays or small coke, and peat. An abundance of coals existed in the neighbourhood: by rejecting those of inferior quality, and coking the others with great care, a combustible was obtained better fitted even than charcoal itself for the fusion of that particular kind of ore which is found in the coal-measures. Thus we find Darby's most favourite charge for his furnaces to have been five baskets of coke, two of brays, and one of peat; next followed the ore, and then the limestone. The use of charcoal was gradually given up as the art of smelting with coke and brays improved, most probably aided by the increased power of the furnace-blast, until at length we find it entirely discontinued.

The castings of Coalbrookdale gradually acquired a reputation, and the trade of Abraham Darby continued to increase until the date of his death, which occurred at Madeley Court in 1717. His sons were too young at the time to carry on the business which he had so successfully started, and several portions of the works were sold at a serious sacrifice. But when the sons had grown up to manhood, they too entered upon the business of iron-founding; and Abraham Darby's son and grandson, both of the same name, largely extended the operations of the firm, until Coalbrookdale, or, as it was popularly called, "Bedlam," became the principal seat of one of the most important branches of the iron trade.

There seems to be some doubt as to the precise time when pit-coal was first regularly employed at Coalbrookdale in smelting the ore. Mr. Scrivenor says, "pit-coal was first used by Mr. Abraham Darby, in his furnace at Coalbrookdale, in 1713;" [4] but we can find no confirmation of this statement in the records of the Company. It is probable that Mr. Darby used raw coal, as was done in the Forest of Dean at the same time,[5] in the process of calcining the ore; but it would appear from his own Memoranda that coke only was used in the process of smelting. We infer from other circumstances that pit-coal was not employed for the latter purpose until a considerably later period. The merit of its introduction, and its successful use in iron-smelting, is due to Mr. Richard Ford, who had married a daughter of Abraham Darby, and managed the Coalbrookdale works in 1747. In a paper by the Rev. Mr. Mason, Woodwardian Professor at Cambridge, given in the 'Philosophical Transactions' for that year,[6] the first account of its successful employment is stated as follows:—"Several attempts have been made to run iron-ore with pit-coal: he (Mr. Mason) thinks it has not succeeded anywhere, as we have had no account of its being practised; but Mr. Ford, of Coalbrookdale in Shropshire, from iron-ore and coal, both got in the same dale, makes iron brittle or tough as he pleases, there being cannon thus cast so soft as to bear turning like wrought-iron." Most probably, however, it was not until the time of Richard Reynolds, who succeeded Abraham Darby the second in the management of the works in 1757, that pit-coal came into large and regular use in the blasting-furnaces as well as the fineries of Coalbrookdale.

Richard Reynolds was born at Bristol in 1735. His parents, like the Darbys, belonged to the Society of Friends, and he was educated in that persuasion. Being a spirited, lively youth, the "old Adam" occasionally cropped out in him; and he is even said, when a young man, to have been so much fired by the heroism of the soldier's character that he felt a strong desire to embrace a military career; but this feeling soon died out, and he dropped into the sober and 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,[7] 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; and the identical words in the above letter were adopted in the specification as descriptive of the process. By this method of puddling, as it is termed, the manufacturer was thenceforward enabled to produce iron in increased quantity at a large reduction in price; and though the invention of the Craneges was greatly improved upon by Onions, and subsequently by Cort, there can be no doubt as to the originality and the importance of their invention. Mr. Tylor states that he was informed by the son of Richard Reynolds that the wrought iron made at Coalbrookdale by the Cranege process "was very good, quite tough, and broke with a long, bright, fibrous fracture: that made by Cort afterwards was quite different." [8] Though Mr. Reynolds's generosity to the Craneges is apparent; in the course which he adopted in securing for them a patent for the invention in their own names, it does not appear to have proved of much advantage to them; and they failed to rise above the rank which they occupied when their valuable discovery was patented. This, however, was no fault of Richard Reynolds, but was mainly attributable to the circumstance of other inventions in a great measure superseding their process, and depriving them of the benefits of their ingenuity.

Among the important improvements introduced by Mr. Reynolds while managing the Coalbrookdale Works, was the adoption by him for the first time of iron instead of wooden rails in the tram-roads along which coal and iron were conveyed from one part of the works to another, as well as to the loading-places along the river Severn. He observed that the wooden rails soon became decayed, besides being liable to be broken by the heavy loads passing over them, occasioning much loss of time, interruption to business, and heavy expenses in repairs. It occurred to him that these inconveniences would be obviated by the use of rails of cast-iron; and, having tried an experiment with them, it answered so well, that in 1767 the whole of the wooden rails were taken up and replaced by rails of iron. Thus was the era of iron railroads fairly initiated at Coalbrookdale, and the example of Mr. Reynolds was shortly after followed on all the tramroads throughout the Country.