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Iron, Steam & Money

Page 10

by Roger Osborne


  As Triewald was trying to promote the engine to his fellow Swedes he was inclined to inflate the effect it had: ‘As the rumour of this magnificent art soon spread all over England, many, who were anxious to make use of this invention at their mines, in the country and abroad, and who exerted themselves to acquire the necessary knowledge for the purpose of constructing a similar wonderful machine, came from all parts of England and abroad to Dudley Castle.’6

  In fact, in view of its historical importance, the engine and its successors were remarkably little reported. And while colliery managers immediately understood its value, the commercial exploitation of the engine was hampered by one important factor. Thomas Savery’s patent of 1698 stated that he had invented the means of ‘raising water by the impellent force of fire’ and this was considered broad enough to encompass Newcomen’s engine, even though the two devices were entirely different. As we have seen, at this time the patent system was still a way of protecting or granting monopolies over entire industries rather than protecting inventions.

  Stephen Switzer wrote in 1729: ‘I am well informed that Mr Newcomen was as early in his Invention as Mr Savery was in his, only the latter being nearer the Court, had obtain’d his Patent before the other knew it, on which account Mr Newcomen was glad to come in as a Partner to it.’7 As Savery’s patent had been extended to 1733, Newcomen was forced to seek the other inventor’s permission to install his engines and to come to an arrangement over payments, the details of which have been lost to history. Only then was Newcomen able to go ahead and start building. From 1712 the spread of his machines was localised but rapid; by 1716 a Newcomen engine was at work at Hawarden in Flintshire; in 1725 Henry Beighton published a map of Warwickshire showing engines at Hawkesbury, Fackley and Griff collieries; and between 1724 and 1727 colliery owner Richard Beach ordered four cast-iron steam engine cylinders from the Coalbrookdale company.

  Rather than constructing them himself, Newcomen sold licences and plans to the builders of these engines. In fact, one of the great attractions of the Newcomen engine (as opposed to the later more sophisticated machines designed by Watt and Trevithick) was that they could be made and maintained by any competent local engineer. An early example of such an arrangement appears in a licence with James Lowther of Whitehaven in Cumbria, dated 10 November 1715: ‘Thomas Newcomen, ironmonger, of Dartmouth, Devon, and others covenanted with Mr Lowther to set up a fire-engine with a steam barrel of at least 16 inches diameter within, and eight feet in length . . . and that such engine had accordingly been erected and since continued to be wrought there.’8

  The parts for the machine were sent by sea from London. At this time the Whitehaven mines had reached a depth of fifty fathoms (300 feet) with the Newcomen engine probably tipping water into an adit halfway up the shaft. Dr William Stukeley described the machine when he visited the site in 1725:

  At last the famous fire-engine discharges the water, which is a notable piece of machinery working itself entirely; it creates a vacuum by first rarefying the air with hot steam, then condenses it suddenly by cold water; whence a piston is drawn up and down alternately, at one end of the beam: this actuates a pump at the other end, which, let down into the works, draws the water out: it makes about fourteen strokes a minute, so that it empties 140 hogsheads in an hour with moderate working.9

  Let us pause here to marvel at this. Even at the very early stages of the machine’s working life, when some historians have characterised it as inefficient, Newcomen had got his engine moving a sixteen-inch-diameter piston through a stroke of eight feet once every four and a half seconds. This was a stupendous engineering achievement, brought about by alternate injections of steam and cold water, using nothing more than the waste coal piled at the pithead; it enabled the engine to pump over 33,000 litres of water every hour. By 1755 the Whitehaven mines were the deepest in the world, using four Newcomen engines to drain a depth of 800 feet.

  In 1714 or 1715 a Newcomen engine was also built at Moor Hall colliery in Leeds, the birthplace of the engineer John Smeaton. Those were the mines that we know, from firm documentary evidence, had Newcomen engines at the time of Thomas Savery’s death in 1715; this was an important date, because the rights in his patent now passed to a syndicate – and the development and spread of Newcomen’s machines had made the Savery patent much more valuable.

  The Newcomen engines now spread across English coalfields and into metal mines in Cornwall and Derbyshire. Often towering above pitheads, they drew a range of curious eighteenth-century travellers. The engine at a lead mine at Yatesstoop in Derbyshire was described by the Reverend James Clegg:

  September 28th 1730 – I set out with Mr Tricket to see some remarkables in several parts of ye Peak . . . came to Winster about noon. Saw 3 curious Engines at work there, which by ye force of fire heating water to vapour a prodigious weight of water was raised from a very great depth, and a vast quantity of lead ore laid dry. The hott vapour ascends from an iron pan, close covered, through a brass cylinder fixed to the top, and by its expanding force raised one end of the engine, which is brought down again by the sudden introduction of a dash of cold water into ye same cylinder which condenseth the vapour. Thus the hott vapour and cold water act by turns, and give ye clearest demonstration of ye mighty elastic force of air.10

  Newcomen left no records of his own work, so we have to appreciate his genius at second hand. He made small additions to his engine design while other engineers improved such things as the shape of the boiler. The admission valve that let steam from the boiler into the cylinder was almost certainly developed by Newcomen and Calley; its intricate mechanism using a tumbling bob is evidence of huge attention to detail by the original pair of workers. Newcomen also developed a mechanism called a buoy which slowed the engine down so that it would not suck too much steam out of the boiler at each stroke, thereby halting the rhythm of the engine. This was present in the Dudley Castle engine, but once boilers were enlarged and improved the buoy became unnecessary. Newcomen was also the first to develop a valve that used gravity acting on a weight to open it, and upward pressure (by steam) to close it. The piston seals were also improved by using hemp rather than leather. New techniques were used in the pumps themselves to cope with the power of the engines. As the rods could be immensely long, timber ‘spears’ or masts were used.

  Engineering firms were well aware that Savery’s patent was to expire in 1733, leaving them free to build their own engines and to make improvements and adaptations. Richard Ford, Abe Darby’s son-in-law and successor as head of the Coalbrookdale Company, wrote to his partner Thomas Goldney in March 1733: ‘As ye patent for ye Fire Engine is about expiring, that business will consequently more increase.’11

  However, the basic Newcomen engine stayed remarkably constant until the revolutionary changes wrought by James Watt. While this was partly due to the social and commercial currents of the time, it seems that Newcomen’s engine was such an enormous leap into the technological future that it took a couple of generations for other engineers to understand fully its technical implications.

  By far the most important adaptation was the widespread use of cast iron rather than brass for cylinders, which allowed them to be made ever bigger: in 1763 a cylinder seventy-four inches in diameter and of ten-and-a-half-feet stroke was built at Coalbrookdale. By then the Northumberland coalfield – the most productive in Britain – was dotted with Newcomen engines. Jesmond, Heaton and Tynemouth collieries each ran four engines, Long Benton five, and Byker six. Using multiple engines increased running costs but on Tyneside coal was extremely cheap. In 1752 the first iron cylinder on Tyneside was installed at Throckley, owned by William Brown, who was the most noted engine builder in the region. This first engine had a gigantic forty-seven-inch-diameter cylinder and Brown put up another twenty-two engines on Tyneside and others in Scotland. He also erected the biggest Newcomen engine ever built: the gigantic seventy-four-inch engine at Walker colliery was fed by four boilers, and its cylinder, whi
ch was built at Coalbrookdale, weighed six and a half tons.

  In 1769 John Smeaton asked William Brown to make a list of the engines in the north of England and Scotland. There were then ninety-nine engines in total; twenty-one had cylinders of sixty inches or greater in diameter, almost certainly all recently made of iron.

  While coal was cheap in collieries and at metal mines near northern coalfields, in the lucrative mining districts of Cornwall it was expensive. But this situation was eased in 1741 when the duty on coal was lifted. While there had been just one Newcomen engine in 1740, William Borlase, the Cornish naturalist, reported thirteen engines in Cornish mines by 1758; in 1769 John Smeaton listed eighteen, and by 1775 there were more than sixty.12 The Cornish connection was crucial for the development of steam power. First, the particular needs of the mines in the south-west of England made Cornish engineers develop their own ideas and adaptations, leading eventually to Richard Trevithick’s revolutionary work. The second reason was Cornwall’s connection to North America.

  One of the main builders of Newcomen engines in the county was the Hornblower family – Jonathan Hornblower together with his sons Jonathan and Josiah. It was Josiah who introduced the atmospheric engine to America via Colonel John Schuyler, who opened a copper mine at North Arlington, New Jersey, in 1715. After sinking a deep shaft in 1735, Schuyler was unable to go deeper due to lying water; he travelled to Cornwall in search of a solution. In 1753 Josiah Hornblower sailed from Falmouth to London, where he oversaw the loading of the components for a Newcomen engine; on 6 June 1753 the Irene sailed, reaching New York in September. The bad weather on the voyage made Hornblower swear he would never sail again, and he stayed in America for the rest of his life. At North Arlington it took eighteen months to quarry the stone to build the engine house, which needed a strong so-called ‘fulcrum wall’ to support the overhead beam, but in March 1755 the first ever steam engine in America was fired up and, with modifications, ran until the early nineteenth century. The lower part of the iron cylinder, thirty inches in diameter and eight feet long, is now in the Smithsonian Institution in Washington. Schuyler would go on to build an engineering works next to the mine and it was here that the first steam engine to be entirely forged and built in America was made.

  Thomas Newcomen died aged sixty-five on 5 August 1729 in London at the lodging house of a Mr Wallin. By that time he had seen his engines installed across a swathe of Britain. He did not outlast the patent taken out by Thomas Savery, nor did he live to see the steam engine take over the world; nevertheless, he had accomplished his aim of devising an engine that would lift water out of mines. He almost certainly did not realise that, in doing so, he laid the grounds for the transformation of human existence. Newcomen was buried, unmarked, in a common vault at Bunhill Fields Nonconformist Cemetery on City Road, Finsbury, London.

  His only obituary appeared in the Monthly Chronicle: ‘About the same time (7 August 1729) died Mr Thomas Newcomen, sole inventor of that surprising machine for raising water by fire.’13

  * * *

  The Engineering Profession

  Accounts of the Industrial Revolution naturally focus on the inventors who made the most important breakthroughs. But thousands of mechanics and engineers were at work in eighteenth-century Britain erecting, maintaining and improving Newcomen engines, building roads, bridges, harbours and canals, and constructing mine workings. Engineering began to be recognised as a profession, with engineers able to turn their hand to a variety of tasks. Engineering, which became a crucial part of Britain’s conversion to an industrial economy, emerged from a generation of artisan mechanics; however, the most distinguished engineer of the time came from a different background.

  John Smeaton was born in Leeds in 1724, attended Leeds Grammar School and entered his father’s law firm. But Smeaton gave up the law in order to pursue his scientific and engineering interests.14 Beginning as a maker of mathematical instruments, he became a skilled and successful engineer, specialising in public works such as harbours, bridges, lighthouses and canals. From the 1750s until his death in 1792 he designed and oversaw a huge array of building projects from the Calder Navigation to Charlestown harbour, including the Eddystone Lighthouse (known as Smeaton’s Tower) which now stands on Plymouth Hoe. He called himself a civil engineer, and was probably the world’s first. What distinguished Smeaton was his interest and skill in pursuing the theoretical and mathematical aspects while also working as a practical engineer. He made significant contributions in every field he investigated; he was elected a fellow of the Royal Society in 1753 and won the Society’s highest award in 1759 for his work on waterwheels and windmills.

  From the 1750s Smeaton began to study Newcomen’s engines and in 1765, at his workshop at Austhorpe, Leeds, he built a working model of an engine incorporating an oscillating wheel instead of a beam, an internal flue in the boiler, and a small but long cylinder. In 1767 he applied the lessons from the model to an engine installed to pump water up to a high-level reservoir at New River Head in Islington, London. The machine didn’t work as well as he hoped, and this provoked Smeaton into undertaking a thorough scientific investigation of all the Newcomen engines in the north of England and Cornwall.

  In order to compare their workings Smeaton invented a standard measurement of their efficiency, which he called the Duty – this was the number of millions of pounds weight of water raised through one foot using one bushel of coal. Smeaton also invented a measure of power, which he called the Great Product – this is the volume of water raised through one foot in one minute. This could be expressed in units of horsepower (a concept developed by James Watt), and Smeaton found that the power of an engine with a seventy-five-inch cylinder was 37.6 h.p., while the sixty-inch cylinder produced 40.8 h.p. Against the received wisdom of the day, he found that a larger cylinder, or even higher pressure exerted by the piston, did not necessarily lead to a higher Duty or Great Product.

  Smeaton saw that the variations in performance could be ironed out by more care being invested in construction, maintenance and operation – using the full length of stroke, firing the boiler correctly, maintaining the cylinder bore, and so on. He adjusted the beam so that the pistons were slightly resistant to the introduction of the steam, which ensured that air did not enter the cylinder at the same time; he increased the height of the cold-water header tank so that the injection of condensing water was a fine spray. The engine water was usually taken direct from the pumped mine water, which led to corrosion and scaling, so Smeaton used only rainwater. He introduced regulatory devices, including a pet-cock to allow in some air when necessary, and a cataract or ‘Jack in the Box’ to make the supply of water intermittent. These enabled the engines to run at less than full load without making them less efficient by, for example, shortening the piston stroke. The first engine built by Smeaton with all these improvements was installed at Long Benton colliery in Northumberland in 1772. The Duty figure was 9.45 million, a huge improvement on the 7.44 million achieved by the most efficient engine. He went on to build other Newcomen engines, including one used to empty the docks at Kronstadt in Russia.

  Other engineers made improvements to the Newcomen engine and adapted it to different uses. Joseph Oxley used a patent ratchet device in 1763 at Hartley colliery in Seaton Delaval, Northumberland, to turn a ‘whim’ or cable drum, but the movement was too irregular so was converted to a waterwheel. John Stewart patented a ratchet in 1766 and in 1768 he built a Newcomen engine in Jamaica to power a sugar mill; all before the breakthrough made by Matthew Wasbrough and James Pickard (see here). Improvements to the boiler by recycling heat were made by James Brindley and Sampson Swaine. All of these preceded the revolution brought about by the work of James Watt; though even during Watt’s dominance of steam power other engineers continued to improve old Newcomen engines. In the 1790s, the firm of Bateman and Sherrat of Salford supplied engines to Lancashire cotton mills with two cylinders working alternately, which drove an overhead ‘rocking shaft’. In 179
5 Hornblower and Maberley connected two cylinders to an overhead pulley, while Francis Thompson of Derbyshire used two forty-inch cylinders, each with a six-foot stroke, arranged vertically with the top one inverted. In 1790 John Curr of Sheffield placed boilers in a separate location at Attercliffe Common colliery.

  All these adaptations and improvements made Newcomen engines more efficient and fit for purpose. However, the combined ingenuity of these and a thousand other engineers could not make the Newcomen engine into a multipurpose power source; to do that took the special genius of James Watt.

  * * *

  8. James Watt’s Revolution

  EVERY SCHOOLCHILD KNOWS that James Watt invented the steam engine. In fact he didn’t, but strangely enough the fact that Watt was not the originator of steam power makes his achievements all the more remarkable. He had the vision and the engineering genius to adapt an engine with limited application, and use it to open the way for the industrialisation of Britain. Watt went well beyond the level of brilliant inventor to become the guiding spirit of the age; he was able to isolate and solve engineering problems in ways that no one else could, and thereby ushered in the powered mechanisation of industry.

  Watt’s role was central because, as we have seen elsewhere, the transition from an advanced organic economy to one based on power derived from fossil fuel was far from inevitable. It took a special combination of scientific curiosity and inventive genius to understand the possibilities that steam power offered, and to work out how to exploit them. Watt was one of the few inventors of the eighteenth century to show an interest in solving theoretical as well as practical problems; this double facility enabled him to meet a series of challenges with apparent ease and dazzling success.1

 

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