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CHAPTER IV.

WATT'S EXPERIMENTS ON STEAM-INVENTS THE
SEPARATE CONDENSER.
 

IT was in the year 1759 that Robison first called the attention of his friend Watt to the subject of the steam-engine.  Robison was then only in his twentieth, and Watt in his twenty-third year.  Robison's idea was that the power of steam might be advantageously applied to the driving of wheel-carriages, and he suggested that it would be most convenient for the purpose to place the cylinder with its open end downwards to avoid the necessity of using a working beam.  Watt admits that he was very ignorant of the steam-engine at that time.  Nevertheless, he began making a model with two cylinders of tin-plate, intending that the pistons and their connecting-rods should act alternately on two pinions attached to the axles of the carriage-wheels.  But the model, being slightly and inaccurately made, did not answer his expectations.  Other difficulties presented themselves, and the scheme was laid aside on Robison leaving Glasgow to go to sea.  Indeed, mechanical science was not yet ripe for the locomotive.  Robison's idea had, however, dropped silently into the mind of his friend, where it grew from day to day, slowly and at length fruitfully.

    At his intervals of leisure and in the quiet of his evenings, Watt continued to prosecute his various studies. He was shortly attracted by the science of chemistry, then in its infancy. Dr. Black was at that time occupied with the investigations which led to his discovery of the theory of latent heat, and it is probable that his familiar conversations with Watt on the subject induced the latter to enter upon a series of experiments with the view of giving the theory some practical direction. His attention again and again reverted to the steam-engine, though he had not yet seen even a model of one. Steam was as yet almost unknown in Scotland as a working power. The first engine was erected at Elphinstone Colliery, in Stirlingshire, about the year 1750; and the second more than ten years later, at Govan Colliery, near Glasgow, where it was known by the startling name of "The Firework." Watt found that the College possessed the model of a Newcomen engine for the use of the Natural Philosophy class, which, at the time of his inquiry, had been sent to London for repair. On hearing of its existence, he suggested to his friend Dr. Anderson, Professor of Natural Philosophy, the propriety of getting back the model; and a sum of money was placed by the Senatus at the Professor's disposal "to recover the steam-engine from Mr. Sisson, instrument maker, in London."
 

    In the meantime Watt sought to learn all that had been written on the subject of the steam-engine.  He ascertained from Desaguliers, from Switzer, and other writers, what had been accomplished by Savery, Newcomen, Beighton and others: and he went on with his own independent experiments.  His first apparatus was of the simplest possible kind.  He used common apothecaries' phials for his steam reservoirs, and canes hollowed out for his steam pipes. [p.81]  In 1761 he proceeded to experiment on the force of steam by means of a small Papin's digester and a syringe.  The syringe was only the third of an inch in diameter, fitted with a solid piston; and it was connected with the digester by a pipe furnished with a stopcock, by which the steam was admitted or shut off at will.  It was also itself provided with a stopcock, enabling a communication to be opened between the syringe and the outer air to permit the steam in the syringe to escape.  The apparatus, though rude, enabled the experimenter to ascertain some important facts.  When the steam in the digester was raised and the cock turned, enabling it to rush against the lower side of the piston, he found that the expansive force of the steam raised a weight of fifteen pounds with which the piston was loaded.  Then, on turning the cock and shutting off the connexion with the digester at the same time that a passage was opened to the air, the steam was allowed to escape, when the weight upon the piston, being no longer counteracted, immediately forced it to descend.

    Watt saw that it would be easy to contrive that the cocks should be turned by the machinery itself instead of by the hand, and the whole be made to work by itself with perfect regularity.  But there was an objection to this method.  Water is converted into vapour as soon as its elasticity is sufficient to overcome the weight of the air which keeps it down.  Under the ordinary pressure of the atmosphere water acquires this necessary elasticity at 212°; but as the steam in the digester was prevented from escaping, it acquired increased heat, and by consequence increased elasticity.  Hence it was that the steam which issued from the digester was not only able to support the piston and the air which pressed upon its upper surface, but the additional load with which the piston was weighted.  With the imperfect mechanical construction, however, of those days, there was a risk lest the boiler should be burst by the steam, which forced its way through the ill-made joints of the machine.  This, conjoined with the great expenditure of steam on the high-pressure system, led Watt to abandon the plan; and the exigencies of his business for a time prevented him pursuing his experiments.

    At length the Newcomen model arrived from London; and, in 1763, the little engine, which was destined to become so famous, was put into the hands of Watt.  The boiler was somewhat smaller than an ordinary tea-kettle.  The cylinder of the engine was only of two inches diameter and six inches stroke.  Watt at first regarded it as merely "a fine play thing."  It was, however, enough to set him upon a track of thinking which led to the most important results.

    When he had repaired the model and set it to work, he found that the boiler, though apparently large enough, could not supply steam in sufficient quantity, and only a few strokes of the piston could be obtained, when the engine stopped.  The fire was urged by blowing, and more steam was produced, but still it would not work properly.

    Exactly at the point at which another man would have abandoned the task in despair, the mind of Watt became thoroughly roused.  "Everything," says Professor Robison, "was to him the beginning of a new and serious study; and I knew that he would not quit it till he had either discovered its insignificance, or had made something of it."  Thus it happened with the phenomena presented by the model of the steam-engine.  Watt referred to his books, and endeavoured to ascertain from them by what means he might remedy the defects which he found in the model; but they could tell him nothing.  He then proceeded with an independent course of experiments, resolved to work out the problem for himself.  In the course of his inquiries he came upon a fact which, more than any other, led his mind into the train of thought which at last conducted him to the invention, of which the results were destined to be so stupendous.  This fact was the existence of Latent Heat.

Ed.—Newcomen pumping engine.  Picture Wikipedia.

    In order to follow the track of investigation pursued by Watt, it is necessary for a moment to revert to the action of the Newcomen pumping-engine.  A beam, moving upon a centre, had affixed to one end of it a chain attached to the piston of the pump, and at the other a chain attached to a piston that fitted into the steam cylinder.  It was by driving this latter piston up and down the cylinder that the pump was worked.  To communicate the necessary movement to the piston, the steam generated in a boiler was admitted to the bottom of the cylinder, forcing out the air through a valve, when its pressure on the under side of the piston counterbalanced the pressure of the atmosphere on its upper side.  The piston, thus placed between two equal forces, was drawn up to the top of the cylinder by the greater weight of the pump gear at the opposite extremity of the beam.  The steam, so far, only discharged the office which was performed by the air it displaced; but, if the air had been allowed to remain, the piston once at the top of the cylinder could not have returned, being pressed as much by the atmosphere underneath as by the atmosphere above it.  The steam, on the contrary, which was admitted by the exclusion of the air, could be condensed, and a vacuum created, by injecting cold water through the bottom of the cylinder.  The piston, being now unsupported, was forced down by the pressure of the atmosphere on its upper surface.  When the piston reached the bottom, the steam was again let in, and the process was repeated.  Such was the engine in ordinary use for pumping water at the time that Watt began his investigations.

    Among his other experiments, he constructed a boiler which showed by inspection the quantity of water evaporated in any given time, and the quantity of steam used in every stroke of the engine.  He was astonished to discover that a small quantity of water in the form of steam heated a large quantity of cold water injected into the cylinder for the purpose of cooling it; and upon further examination he ascertained that steam heated six times its weight of cold water down to 212°, which was the temperature of the steam itself.  "Being struck with this remarkable fact," says Watt, "and not understanding the reason of it, I mentioned it to my friend Dr. Black, who then explained to me his doctrine of latent heat, which he had taught for some time before this period (the summer of 1764); but having myself been occupied by the pursuits of business, if I had heard of it I had not attended to it, when I thus stumbled upon one of the material facts by which that beautiful theory is supported."

    When Watt found that water, in its conversion into vapour, became such a reservoir of heat, he was more than ever bent on economising it; for the great waste of heat, involving so heavy a consumption of fuel, was felt to be the principal obstacle to the extended employment of steam as a motive power.  He accordingly endeavoured, with the same quantity of fuel, at once to increase the production of steam, and to diminish its waste.  He increased the heating surface of the boiler by making flues through it; he surrounded his boiler with wood, as being a worse conductor of heat than the brickwork which surrounds common furnaces; and he cased the cylinders and all the conducting-pipes in materials which conducted heat very slowly.  But none of these contrivances were effectual; for it turned out that the chief expenditure of steam, and consequently of fuel, in the Newcomen engine was occasioned by the re-heating of the cylinder after the steam had been condensed by the cold water admitted into it.  Nearly four-fifths of the whole steam employed was condensed on its first admission, before the surplus could act upon the piston.

    Watt therefore came to the conclusion that to make a perfect steam-engine it was necessary that the cylinder should be always as hot as the steam that entered it; but it was equally necessary that the steam should be condensed when the piston descended—nay, that it should be cooled down below 100°, or a considerable amount of vapour would be given off, which would resist the descent of the piston, and diminish the power of the engine.  Thus the cylinder was never to be at a less temperature than 212°, and yet at each descent of the piston it was to be less than 100°; conditions which, on the very face of them, seemed to be wholly incompatible.

    We revert for a moment to the progress of Watt's instrument-making business.  The shop in the College was not found to answer, being too far from the principal thoroughfares.  If he wanted business he must go nearer to the public, for it was evident that they would not come to him.  But to remove to a larger shop, in a more central quarter, involved an expenditure of capital for which he was himself unequal.  His father had helped him with money as long as he could, but could do so no longer.  He had grown poor by his losses, and, instead of giving his son help, needed help himself.  Watt therefore looked about him for a partner with some means, and succeeded in finding one in a Mr. John Craig; in conjunction with whom he opened a retail shop in the Salt-market, nearly opposite St. Andrew's Street, about the year 1760; removing from thence to Buchanan's Land, on the north side of the Trongate, a few years later. [p.87]  Watt's partner was not a mechanic, but he supplied the requisite capital, and attended to the books.  The partnership was on the whole successful, as we infer from the increased number of hands employed.  At first Watt could execute all his orders himself, and afterwards by the help of a man and a boy; but by the end of 1764 the number of hands employed by the firm had increased to sixteen.

    His improving business brought with it an improving income, and Watt—always a frugal and thrifty man—began to save a little money.  He was encouraged to economise by another circumstance—his intended marriage with his cousin, Margaret Miller.  In anticipation of this event, he had removed from his rooms in the College to a house in Delftfield Lane—a narrow passage then parallel with York Street, but now converted into the spacious thoroughfare of Watt Street.  Having furnished his house in a plain yet comfortable style, he brought home his young wife, and installed her there in July, 1764.  The step was one of much importance to his personal well-being.  Mrs. Watt was of a lively, cheerful temperament and as Watt himself was of a meditative disposition, prone to melancholy, and a frequent sufferer from nervous headache, her presence at his fireside could not fail to have a beneficial influence upon his health and comfort.

    Watt continued to pursue his studies as before.  Though still occupied with his inquiries and experiments as to steam, he did not neglect his proper business, but was constantly on the look-out for improvements in instrument making.  A machine which he invented for drawing in perspective proved a success; and he made a considerable number of them to order for customers in London as well as abroad.  He was also an indefatigable reader, and continued to extend his knowledge of chemistry and mechanics by perusal of the best books on these sciences.

    Above all other subjects, however, the improvement of the steam-engine continued to keep the fastest hold upon his mind.  He still brooded over his experiments with the Newcomen model, but did not seem to make much way in introducing any practical improvement in its mode of working.  His friend Robison says he struggled long to condense with sufficient rapidity without injection, trying one expedient after another, finding out what would do by what would not do, and exhibiting many beautiful specimens of ingenuity and fertility of resource.  He continued, to use his own words, "to grope in the dark, misled by many an ignis fatuus."  It was a favourite saying of his that "Nature has a weak side, if we can only find it out;" and he went on groping and feeling for it, but as yet in vain.  At length light burst upon him, and all at once the problem over which he had been brooding was solved.

    One Sunday afternoon, in the spring of 1765, he went to take an afternoon walk on the Green, then a quiet, grassy meadow, used as a bleaching and grazing ground.  On week-days the Glasgow lasses came thither with their largest kail-pots, to boil their clothes in; and sturdy queans might be seen, with coats kilted, tramping blankets in their tubs.  On Sundays the place was comparatively deserted, and hence Watt went thither to take a quiet afternoon stroll.  His thoughts were as usual running on the subject of his unsatisfactory experiments with the Newcomen engine, when the first idea of the separate condenser suddenly flashed upon his mind.  But the notable discovery is best told in his own words, as related to Mr. Robert Hart many years after:—

    "I had gone to take a walk on a fine Sabbath afternoon.  I had entered the Green by the gate at the foot of Charlotte Street, and had passed the old washing-house.  I was thinking upon the engine at the time, and had gone as far as the herd's house, when the idea came into my mind that as steam was an elastic body it would rush into a vacuum, and if a communication were made between the cylinder and an exhausted vessel, it would rush into it, and might be there condensed without cooling the cylinder.  I then saw that I must get rid of the condensed steam and injection water if I used a jet, as in Newcomen's engine.  Two ways of doing this occurred to me.  First, the water might be run off by a descending pipe, if an off-let could be got at the depth of 35 or 36 feet, and any air might be extracted by a small pump.  The second was to make the pump large enough to extract both water and air."  He continued: "I had not walked further than the Golf-house [p.90-1] when the whole thing was arranged in my mind." [p.90-2]

    Great and prolific ideas are almost always simple.  What seems impossible at the outset appears so obvious when it is effected that we are prone to marvel that it did not force itself at once upon the mind.  Late in life Watt, with his accustomed modesty, declared his belief that if he had excelled it had been by chance and the neglect of others.  To Professor Jardine he said "that when it was analysed, the invention would not appear so great as it seemed to be.  In the state," said he, "in which I found the steam-engine, it was no great effort of mind to observe that the quantity of fuel necessary to make it work would for ever prevent its extensive utility.  The next step in my progress was equally easy—to inquire what was the cause of the great consumption of fuel: this, too, was readily suggested, viz., the waste of fuel which was necessary to bring the whole cylinder, piston, and adjacent parts from the coldness of water to the heat of steam, no fewer than from fifteen to twenty times in a minute."  The question then occurred, how was this to be avoided or remedied?  It was at this stage that the idea of carrying on the condensation in a separate vessel flashed upon his mind, and solved the difficulty.

    Mankind has been more just to Watt than he was to himself.  There was no accident in the discovery.  It was the result of close and continuous study; and the idea of the separate condenser was merely the last step of a long journey—a step which could not have been taken unless the road which led to it had been carefully and thoughtfully traversed.  Dr. Black says, "This capital improvement flashed upon his mind at once, and filled him with rapture"; a statement which, spite of the unimpassioned nature of Watt, we can readily believe.
 

    On the morning following his Sunday afternoon's walk on Glasgow Green, Watt was up betimes making arrangements for a speedy trial of his new plan.  He borrowed from a college friend a large brass syringe, an inch and a third in diameter, and ten inches long, of the kind used by anatomists for injecting arteries with wax previous to dissection.  The body of the syringe served for a cylinder, the piston-rod passing through a collar of leather in its cover.  A pipe connected with the boiler was inserted at both ends for the admission of steam, and at the upper end was another pipe to convey the steam to the condenser.  The axis of the stem of the piston was drilled with a hole, fitted with a valve at its lower end, to permit the water produced by the condensed steam on first filling the cylinder to escape.  The first condenser made use of was an improvised cistern of tinned plate, provided with a pump to get rid of the water formed by the condensation of the steam, both the condensing-pipes and the air-pump being placed in a reservoir of cold water.

    "The steam-pipe," says Watt, "was adjusted to a small boiler.  When steam was produced, it was admitted into the cylinder, and soon issued through the perforation of the rod, and at the valve of the condenser; when it was judged that the air was expelled, the steam-cock was shut, and the air-pump piston-rod was drawn up, which leaving the small pipes of the condenser in a state of vacuum, the steam entered them and was condensed.  The piston of the cylinder immediately rose and lifted a weight of about 18 lbs., which was hung to the lower end of the piston-rod.  The exhaustion-cock was shut, the steam was re-admitted into the cylinder, and the operation was repeated.  The quantity of steam consumed and the weights it could raise were observed, and, excepting the non-application of the steam-case and external covering, the invention was complete, in so far as regarded the savings of steam and fuel."

    But, although the invention was complete in Watt's mind, it took him many long and laborious years to work out the details of the engine.  His friend Robison, with whom his intimacy was maintained during these interesting experiments, has given a graphic account of the difficulties which he successively encountered and overcame.  He relates that on his return from the country, after the College vacation in 1765, he went to have a chat with Watt and communicate to him some observations he had made on Desagulier's and Belidor's account of the steam-engine.  He went straight into the parlour, without ceremony, and found Watt sitting before the fire looking at a little tin cistern which he had on his knee.  Robison immediately started the conversation about steam, his mind, like Watt's, being occupied with the means of avoiding the excessive waste of heat in the Newcomen engine.  Watt, all the while, kept looking into the fire, and after a time laid down the cistern at the foot of his chair, saying nothing.  It seems that Watt felt rather nettled at Robison having communicated to a mechanic of the town a contrivance which he had hit upon for turning the cocks of his engine.  When Robison therefore pressed his inquiry, Watt at length looked at him and said briskly, "You need not fash yourself any more about that, man; I have now made an engine that shall not waste a particle of steam.  It shall all be boiling hot,—ay, and hot water injected, if I please."  He then pushed the little tin cistern with his foot under the table.

    Robison could learn no more of the new contrivance from Watt at that time; but on the same evening he accidentally met a mutual acquaintance, who, supposing he knew as usual the progress of Watt's experiments, observed to him, "Well, have you seen Jamie Watt?"  "Yes."  "He'll be in fine spirits now with his engine?"  "Yes," said Robison, "very fine spirits."  "Gad!" said the other, "the separate condenser's the very thing: keep it but cold enough, and you may have a perfect vacuum, whatever be the heat of the cylinder."  This was Watt's secret, and the nature of the contrivance was clear to Robison at once.

    It will be observed that Watt had not made a secret of it to his other friends.  Indeed Robison himself admitted that one of Watt's greatest delights was to communicate the results of his experiments to others, and set them upon the same road to knowledge with himself; and that no one could display less of the small jealousy of the tradesman than he did.  To his intimate friend, Dr. Black, he communicated the progress made by him at every stage; and the Doctor kindly encouraged him in his struggles, cheered him in his encounter with difficulty, and, what was of still more practical value at the time, he helped him with money to enable him to prosecute his invention.

    Communicative though Watt was disposed to be, he learnt reticence when he found himself exposed to the depredations of the smaller fry of inventors.  Robison says that had he lived in Birmingham or London at the time, the probability is that some one or other of the numerous harpies who live by sucking other people's brains would have secured patents for his more important inventions, and thereby deprived him of the benefits of his skill, science, and labour.  As yet, however, there were but few mechanics in Glasgow capable of understanding or appreciating the steam-engine; and the intimate friends to whom he freely spoke of his discovery were too honourable-minded to take advantage of his confidence.  Shortly after, Watt fully communicated to Robison the different stages of his invention, and the results at which he had arrived—much to the delight of his friend.

    It will be remembered that in the Newcomen engine the steam was only employed for the purpose of producing a vacuum, and that its working power was in the down stroke, which was effected by the pressure of the air upon the piston; hence it is now usual to call it the Atmospheric engine.  Watt perceived that the air which followed the piston down the cylinder would cool the latter, and that steam would be wasted in re-heating it.  In order, therefore, to avoid this loss of heat, he resolved to put an air-tight cover upon the cylinder, with a hole and stuffing-box for the piston-rod to slide through, and to admit steam above the piston, to act upon it instead of the atmosphere.  When the steam had done its duty in driving down the piston, a communication was opened between the upper and lower part of the cylinder, and the same steam, distributing itself equally in both compartments, sufficed to restore equilibrium.  The piston was now drawn up by the weight of the pump-gear; the steam beneath it was then condensed in the separate vessel so as to produce a vacuum, and a fresh jet of steam from the boiler was let in above the piston, which forced it again to the bottom of the cylinder.  From an atmospheric it had thus become a true steam engine, and with a much greater economy of steam than when the air did half the duty.  But it was not only important to keep the air from flowing down the inside of the cylinder: the air which circulated within cooled the metal and condensed a portion of the steam within; and this Watt proposed to remedy by a second cylinder, surrounding the first with an interval between the two which was to be kept full of steam.

    One by one these various contrivances were struck out, modified, settled, and reduced to definite plans; the separate condenser, the air and water pumps, the use of fat and oil (instead of water as in the Newcomen engine) to keep the piston working in the cylinder air-tight, and the enclosing of the cylinder itself within another to prevent the loss of heat.  They were all but emanations from the first idea of inventing an engine working by a piston in which the cylinder should be kept continually hot and perfectly dry.  "When once," says Watt, "the idea of separate condensation was started, all these improvements followed as corollaries in quick succession; so that in the course of one or two days the invention was thus far complete in my mind." [p.97]

    The next step was to construct a model engine for the purpose of embodying the invention in a working form.  With this object Watt hired an old cellar, situated in the first wide entry to the north of the beef-market in King-street, and there proceeded with his model.  He found it much easier, however, to prepare his plan than to execute it.  Like most ingenious and inventive men, Watt was extremely fastidious; and this occasioned considerable delay in the execution of the work.  His very inventiveness to some extent proved a hindrance; for new expedients were perpetually occurring to him, which he thought would be improvements, and which he, by turns, endeavoured to introduce.  Some of these expedients he admits proved fruitless, and all of them occasioned delay.  Another of his chief difficulties was in finding competent workmen to execute his plans.  He himself had been accustomed only to small metal work, with comparatively delicate tools, and had very little experience "in the practice of mechanics in great," as he termed it.  He was therefore under the necessity of depending, in a great measure, upon the handiwork of others.  Mechanics capable of working out Watt's designs in metal were scarcely to be found at that time in Scotland.  The beautiful self-acting tools and workmanship which have since been called into being, principally by his own invention, did not then exist.  The only available hands in Glasgow were the blacksmiths and tinners, little capable of constructing articles out of their ordinary business; and even in these they were found clumsy, blundering, and incompetent.  The result was, that in consequence of the malconstruction of the larger parts, Watt's first model was only partially successful.  The experiments made with it, however, served to verify the expectations he had formed, and to place the advantages of the invention beyond the reach of doubt.  On the exhausting-cock being turned, the piston, when loaded with 18 lbs., ascended as quick as the blow of a hammer; and the moment the steam-cock was opened, it descended with like rapidity, though the steam was weak, and the machine snifted at many openings.

    Satisfied that he had laid hold of the right principle of a working steam-engine, Watt felt impelled to follow it to an issue.  He could give his mind to no other business in peace until this was done.  He wrote to a friend that he was quite barren on every other subject.  "My whole thoughts," said he, "are bent on this machine.  I can think of nothing else." [p.99]  He proceeded to make another and bigger, and, he hoped, a satisfactory engine in the following August; and with that object he removed from the old cellar in King-street to a larger apartment in the then disused pottery or delftwork near the Broomielaw.  There he shut himself up with his assistant, John Gardiner, for the purpose of erecting his engine.  The cylinder was five or six inches in diameter, with a two-feet stroke.  The inner cylinder was enclosed in a wooden steam-case, and placed inverted, the piston working through a hole in the bottom of the steam-case.  After two months' continuous application and labour it was finished and set to work; but it leaked in all directions, and the piston was far from air-tight.  The condenser also was in a bad way, and needed many alterations.  Nevertheless, the engine readily worked with 10½ lbs. pressure on the inch, and the piston lifted a weight of 14 lbs.

    The improvement of the cylinder and piston continued Watt's chief difficulty, and taxed his ingenuity to the utmost.  At so low an ebb was the art of making cylinders that the one he used was not bored but hammered, the collective mechanical skill of Glasgow being then unequal to the boring of a cylinder of the simplest kind; nor, indeed, did the necessary appliances for the purpose exist anywhere else.  In the Newcomen engine a little water was poured upon the upper surface of the piston, and sufficiently filled up the interstices between the piston and the cylinder.  But when Watt employed steam to drive down the piston, he was deprived of this resource, for the water and the steam could not coexist.  Even if he had retained the agency of the air above, the drip of water from the crevices into the lower part of the cylinder would have been incompatible with keeping the surface hot and dry, and, by turning into vapour as it fell upon the heated metal, it would have impaired the vacuum during the descent of the piston.

    While he was occupied with this difficulty, and striving to overcome it by the adoption of new expedients, such as leather collars and improved workmanship, he wrote to a friend, "My old white-iron man is dead"; the old white-iron man, or tinner, being his leading mechanic.  Unhappily, also, just as he seemed to have got the engine into working order, the beam broke, and having great difficulty in replacing the damaged part, the accident threatened, together with the loss of his best workman, to bring the experiment to an end.  But though discouraged by these misadventures, he was far from defeated, but went on as before, battling down difficulty inch by inch, and holding good the ground he had won, becoming every day more strongly convinced that he was in the right track, and that the important uses of his invention, could he but find time and means to perfect it, were beyond the reach of doubt.

    But how to find the means!  Watt himself was a comparatively poor man.  He had no money but what he earned by his business of mechanical instrument making, which he had for some time been neglecting through his devotion to the construction of his engine.  What he wanted was capital, or the help of a capitalist willing to advance the necessary funds to perfect his invention.  To give a fair trial to the new apparatus would involve an expenditure of several thousand pounds; and who on the spot could be expected to invest so large a sum in trying a machine so entirely new, depending for its success on physical principles so very imperfectly understood?

    There was no such help to be found in Glasgow.  The tobacco lords, though rich, took no interest in steam power and the manufacturing class, though growing in importance, had full employment for their little capital in their own concerns.

――――♦――――

 
CHAPTER V.

WATT'S CONNEXION WITH DR. ROEBUCK—WATT
ACTS AS SURVEYOR AND ENGINEER.

DR. BLACK continued to take a lively interest in Watt's experiments, and lent him occasional sums of money from time to time to enable him to prosecute them to an issue.  But the Doctor's means were too limited to permit him to do more than supply Watt's more pressing necessities.  Meanwhile, the debts which the latter had already incurred, small though they were in amount, hung like a millstone round his neck.  Black then bethought him whether it would not be possible to associate Watt with some person possessed of sufficient means, and of an active commercial spirit, who should join as a partner in the risk, and share in the profits of the enterprise.  Such a person, he thought, was Dr. Roebuck, the founder of the Carron Iron Works, an enterprising man, of undaunted spirit, not scared by difficulties, nor a niggard of expense when he saw before him any reasonable prospect of advantage. [p.102]

    Roebuck was at that time engaged in sinking for coal on a large scale near Boroughstoness, where he experienced considerable difficulty in keeping the shafts clear of water.  The Newcomen engine, which he had erected, was found comparatively useless, and he was ready to embrace any other scheme which held out a reasonable prospect of success.  Accordingly, when his friend Dr. Black informed him of an ingenious young mechanic at Glasgow who had invented a steam-engine, capable of working with increased power, speed, and economy, Roebuck immediately felt interested and entered into correspondence with Watt on the subject.  He was at first somewhat sceptical as to the practicability of the new engine, so different in its action from that of Newcomen; and he freely stated his doubts to Dr. Black.  He was under the impression that condensation might in some way be effected in the cylinder without injection; and he urged Watt to try whether this might not be done.  Contrary to his own judgment, Watt tried a series of experiments with this object, and at last abandoned them, Roebuck himself admitting his error.

    Up to this time Watt and Roebuck had not met, though they carried on a long correspondence on the subject of the engine.  In September, 1765, we find Roebuck inviting Watt to come over with Dr. Black to Kinneil (where Roebuck lived), and discuss with him the subject of the engine.  Watt wrote to say that "if his foot allowed him" he would visit Carron on a certain day,—from which we infer that he intended to walk.  But the way was long and the road miry, and Watt could not then leave his instrument shop; so the visit was postponed.  In the meantime Roebuck urged Watt to press forward his invention with all speed, "whether he pursued it as a philosopher or as a man of business."

    In the month of November following Watt forwarded to Roebuck the detailed drawings of a covered cylinder and piston to be cast at the Carron Works.  Though the cylinder was the best that could be made there, it was very ill-bored, and was eventually laid aside as useless.  The piston-rod was made at Glasgow, under Watt's own supervision; and when it was completed he was afraid to send it on a common cart, lest the workpeople should see it, which would "occasion speculation."  "I believe," he wrote in July, 1766, "it would be best to send it in a box."  These precautions would seem to have been dictated, in some measure, by fear of piracy; and it is obvious that the necessity of acting by stealth increased the difficulty of getting the various parts of the proposed engine constructed.  Watt's greatest obstacle continued to be the clumsiness and inexpertness of his mechanics.  "My principal hindrance in erecting engines," he wrote to Roebuck, "is always the smith-work."

    In the meantime it was necessary for Watt to attend to the maintenance of his family.  He found that the steam-engine experiments brought nothing in, while they were a constant source of expense.  Besides, they diverted him from his retail business, which needed constant attention.  It ought also to be mentioned that, his partner having lately died, the business had been somewhat neglected and had consequently fallen off.  At length he determined to give it up altogether, and to begin the business of a surveyor.  He accordingly removed from the shop in Buchanan's Land to an office on the east side of King-street a little south of Prince's-street.  It would appear that he succeeded in obtaining a fair share of business in his new vocation.  He already possessed a sufficient knowledge of surveying from the study of the instruments which it had been his business to make; and application and industry did the rest.  His first jobs were in surveying lands, defining boundaries, and surveyor's work of the ordinary sort; from which he gradually proceeded to surveys of a more important character.

    It affords some indication of the local estimation in which Watt was held that the magistrates of Glasgow should have selected him as a proper person to survey a canal for the purpose of opening up a new coal-field in the neighbourhood, and connecting it with the city, with a view to a cheaper and more abundant supply of fuel.  He also surveyed a ditch-canal for the purpose of connecting the rivers Forth and Clyde, by what was called the Loch Lomond passage; though the scheme of Brindley and Smeaton was eventually preferred as the more direct line.  Watt came up to London in 1767, in connection with the application to Parliament for powers to construct his canal; and he seems to have been very much disgusted with the proceedings before "the confounded committee of Parliament," as he called it; adding, "I think I shall not wish to have anything to do with the House of Commons again.  I never saw so many wrong-headed people on all sides gathered together."  The fact, however, that they had decided against him had probably some share in leading him to form this opinion as to the wrongheadedness of the Parliamentary Committee.

    Though interrupted by indispensable business of this sort, Watt proceeded with the improvement of his steam-engine whenever leisure permitted.  Roebuck's confidence in its eventual success was such that in 1767 he undertook to pay debts to the amount of £1,000 which Watt had incurred in prosecuting his project up to that time, and also to provide the means of prosecuting further experiments, as well as to secure a patent for the engine.  In return for this outlay Roebuck was to have two-thirds of the property in the invention.  Early in 1768 Watt made trial of a new and larger model, with a cylinder of seven or eight inches diameter.  But the result was not very satisfactory.  "By an unforeseen misfortune," he wrote to Roebuck, "the mercury found its way into the cylinder, and played the devil with the solder.  This throws us back at least three days, and is very vexatious, especially as it happened in spite of the precautions I had taken to prevent it."  Roebuck, becoming impatient, urged Watt to meet him to talk the matter over; and suggested that as Watt could not come as far as Carron, they should meet at Kilsyth, about fifteen miles from Glasgow.  Watt replied, saying he was too unwell to be able to ride so far, and that his health was such that the journey would disable him from doing anything for three or four days after.  But he went on with his experiments, patching up his engine, and endeavouring to get it into working condition.  After about a month's labour he at last succeeded to his heart's content; and he at once communicated the news to his partner, intimating his intention of at last paying his long-promised visit to Roebuck at Kinneil.  "I sincerely wish you joy of this successful result," he said, "and hope it will make some return for the obligations I owe you."

    Kinneil House, to which Watt hastened to pay his visit of congratulation to Dr. Roebuck, is an old-fashioned building, somewhat resembling an old French chateau.  It was a former country-seat of the Dukes of Hamilton, and is finely situated on the shores of the Frith of Forth.  The mansion is rich in classical associations, having been inhabited, since Roebuck's time, by Dugald Stewart, who wrote in it his 'Philosophy of the Human Mind.'  There he was visited by Wilkie, the painter, when in search of subjects for his pictures; and Dugald Stewart found for him, in an old farmhouse in the neighbourhood, the cradle-chimney introduced in the "Penny Wedding."  But none of these names can stand by the side of that of Watt; and the first thought at Kinneil, of every one who is familiar with his history, would be of the memorable day when he rode over in exultation to wish Dr. Roebuck joy of the success of the steam-engine.  His note of triumph was, however, premature.  He had yet to suffer many sickening delays and bitter disappointments; for, though he had contrived to get his model executed with fair precision, the skill was still wanting to manufacture the parts of their full size with the requisite unity; and his present elation was consequently doomed to be succeeded by repeated discomfiture.

    The model went on so well, however, that it was determined at once to take out a patent for the engine.  The first step was to secure its provisional protection, and with that object Watt went to Berwick-upon-Tweed, and made a declaration before a Master in Chancery of the nature of the invention.  In August, 1768, we find him in London on the business of the patent.  He became utterly wearied with the delays interposed by sluggish officialism, and disgusted with the heavy fees which he was required to pay in order to protect his invention.  He wrote home to his wife at Glasgow in a very desponding mood.  Knowing her husband's diffidence and modesty, but having the fullest confidence in his genius, she replied, "I beg that you will not make yourself uneasy, though things should not succeed to your wish.  If it [the condensing engine] will not do, something else will; never despair."  Watt must have felt cheered by these brave words of his noble helpmate, and encouraged to go onward cheerfully in hope.

    He could not, however, shake off his recurring fits of despondency, and on his return to Glasgow we find him occasionally in very low spirits.  Though his head was full of his engine, his heart ached with anxiety for his family, who could not be maintained on hope, already so long deferred.  The more sanguine Roebuck was elated with the good working of the model, and impatient to bring the invention into practice.  He wrote Watt in October, 1768, "You are now letting the most active part of your life insensibly glide away.  A day, a moment, ought not to be lost.  And you should not suffer your thoughts to be diverted by any other object, or even improvement of this, but only the speediest and most effectual manner of executing an engine of a proper size, according to your present ideas."

    Watt, however, felt that his invention was capable of many improvements, and he was never done introducing new expedients.  He proceeded, in the intervals of leisure which he could spare from his surveying business, to complete the details of the drawings and specification,—making various trials of pipe-condensers, plate-condensers, and drum-condensers,—contriving steam-jackets to prevent the waste of heat and new methods for securing greater tightness of the piston,—inventing condenser-pumps, oil-pumps, gauge-pumps, exhausting-cylinders, loading-valves, double cylinders, beams, and cranks.  All these contrivances had to be thought out and tested, elaborately and painfully, amidst many failures and disappointments; and Dr. Roebuck began to fear that the fresh expedients which were always starting up in Watt's brain would endlessly protract the consummation of the invention.  Watt, on his part, felt that he could only bring the engine nearer to perfection by never resting satisfied with imperfect devices, and hence he left no means untried to overcome the many practical defects in it of which he was so conscious.  Long after, when a noble lord was expressing to him the admiration with which he regarded his great achievement, Watt replied: "The public only look at my success, and not at the intermediate failures and uncouth constructions which have served me as so many steps to climb to the top of the ladder."

    As to the lethargy from which Roebuck sought to raise Watt, it was merely the temporary reaction of a mind strained and wearied with long-continued application to a single subject, and from which it seemed to be occasionally on the point of breaking down altogether.  To his intimate friends, Watt bemoaned his many failures, his low spirits, his bad health, and his sleepless nights.  He wrote to his friend Dr. Small [p.111] in January, 1769, "I have many things I could talk to you about—much contrived, and little executed.  How much would good health and spirits be worth to me!"  A month later he wrote, "I am still plagued with head-aches, and sometimes heart-aches."

    It is nevertheless a remarkable proof of Watt's indefatigable perseverance in his favourite pursuit, that at this very time, when apparently sunk in the depths of gloom, he learnt German for the purpose of getting at the contents of a curious book, the Theatrum Machinarum of Leupold, which just then fell into his hands, and contained an account of the machines, furnaces, methods of working, profits, &c., of the mines in the Upper Hartz.  His instructor in the language was a Swiss dyer, settled in Glasgow.  With the like object of gaining access to untranslated books in French and Italian—then the great depositories of mechanical and engineering knowledge—Watt had already mastered both these languages.

    In preparing his specification, Watt viewed the subject in all its bearings.  The production of power by steam is a very large one, but Watt grasped it thoroughly.  The insight with which he searched, analysed, arranged, and even provided for future modifications, was the true insight of genius.  He seems with an almost prophetic eye to have seen all that steam was capable of accomplishing.  This is well illustrated by his early plan of working steam expansively by cutting it off at about half-stroke, thereby greatly economising its use; as well as by his proposal to employ high-pressure steam where cold water could not be used for purposes of condensation. [p.111]  The careful and elaborate manner in which he studied the specification, and the consideration which he gave to each of its various details, are clear from his correspondence with Dr. Small, which is peculiarly interesting, as showing Watt's mind actively engaged in the very process of invention.  At length the necessary specification and drawings were completed and lodged early in 1769,—a year also memorable as that in which Arkwright took out the patent for his spinning-machine.

    In order to master thoroughly the details of the ordinary Newcomen engine, and to ascertain the extent of its capabilities as well as of its imperfections, Watt undertook the erection of several engines of this construction; and during his residence at Kinneil took charge of the Schoolyard engine near Boroughstoness, in order that he might thereby acquire a full practical knowledge of its working.  Mr. Hart, in his interesting 'Reminiscences of James Watt,' gives the following account.  "My late brother had learned from an old man who had been a workman at Dr. Roebuck's coal-works when Mr. Watt was there, that he had erected a small engine on a pit they called Taylor's Pitt.  The workman could not remember what kind of engine it was, but it was the fastest-going one he ever saw.  From its size, and from its being placed in a small timber-house, the colliers called it the 'Box Bed.'  We thought it likely to have been the first of the patent engines made by Mr. Watt, and took the opportunity of mentioning this to him at our interview.  He said he had erected that engine, but he did not wish at the time to venture on a patent one until he had a little more experience."

    At length he proceeded to erect the trial-engine after his new patent, and made arrangements to stay at Kinneil until the work was finished.  It had been originally intended to erect it in the little town of Boroughstoness; but as prying eyes might have watched his proceedings there, and as he wished to avoid display, being determined, as he said, "not to puff," he fixed upon an outhouse behind Kinneil, close by the burnside in the glen, where there was abundance of water and secure privacy.  The materials were brought to the place, partly from Watt's small works at Glasgow, and partly from Carron, where the cylinder—of eighteen inches diameter and five feet stroke—had been cast and a few workmen were placed at his disposal.
 

    The process of erection was very tedious, owing to the clumsiness of the mechanics employed on the job.  Watt was occasionally compelled to be absent on other business, and on his return he usually found the men at a standstill, not knowing what to do next.  As the engine neared completion, his "anxiety for his approaching doom" kept him sleepless at nights; for his fears were more than equal to his hopes.  He was easily cast down by little obstructions, and especially discouraged by unforeseen expense.  Roebuck, on the contrary, was hopeful and energetic, and often took occasion to rally the other on his despondency under difficulties, and his almost painful want of confidence in himself.  Roebuck was, doubtless, of much service to Watt in encouraging him to proceed with his invention, and also in suggesting some important modifications in the construction of the engine.  It is probable, indeed, that, but for his help, Watt could not have gone on.  Robison says, "I remember Mrs. Roebuck remarking one evening, 'Jamie is a queer lad, and, without the Doctor, his invention would have been lost; but Dr. Roebuck won't let it perish.'"

    The new engine, on which Watt had expended so much labour, anxiety, and ingenuity, was completed in September, 1759, about six months after the date of its commencement.  But its success was far from decided.  Watt himself declared it to be "a clumsy job."  His new arrangement of the pipe-condenser did not work well; and the cylinder, having been badly cast, was found almost useless.  One of his greatest difficulties consisted in keeping the piston tight.  He wrapped it round with cork, oiled rags, tow, old hat, paper, horse-dung, and other things, but still there were open spaces left, sufficient to let the air in and the steam out.  Watt was grievously depressed by his want of success, and he had serious thoughts of giving up the thing altogether.  Before abandoning it, however, the engine was again thoroughly overhauled, many improvements were introduced in it, and a new trial was made of its powers.  But this did not prove more successful than the earlier ones had been.  "You cannot conceive," he wrote to Small, "how mortified I am with this disappointment.  It is a damned thing for a man to have his all hanging by a single string.  If I had wherewithal to pay the loss, I don't think I should so much fear a failure but I cannot bear the thought of other people becoming losers by my schemes; and I have the happy disposition of always painting the worst."

    Watt was therefore bound to prosecute his project by honour, not less than by interest; and summoning up his courage, he went on with it anew.  He continued to have the same confidence as ever in the principles of his engine: where it broke down, it was in workmanship.  Could mechanics but be found capable of accurately executing its several parts, he believed that its success was certain.  But no such mechanics were to be found at Carron.

    By this time Roebuck was becoming embarrassed with debt, and involved in various difficulties.  The pits were drowned with water, which no existing machinery could pump out, and ruin threatened to overtake him before Watt's engine could come to his help.  He had sunk in the coalmine, not only his own fortune, but much of the property of his relatives; and he was so straitened for money that he was unable to defray the cost of taking out the patent according to the terms of his engagement, and Watt had accordingly to borrow the necessary money from his never-failing friend, Dr. Black.  He was thus adding to his own debts, without any clearer prospect before him of ultimate relief.  No wonder that he should, after his apparently fruitless labour, express to Small his belief that, "of all things in life, there is nothing more foolish than inventing."  The unhappy state of his mind may be further inferred from his lamentation expressed to the same friend on the 31st of January, 1770.  "To-day," said he, "I enter the thirty-fifth year of my life, and I think I have hardly yet done thirty-five pence worth of good in the world; but I cannot help it."

    Notwithstanding the failure of his engine thus far, and the repeated resolution expressed to Small that he would invent no more, leading, as inventing did, only to vexation, failure, loss, and increase of headache, Watt could not control his irrepressible instinct to invent; and whether the result might be profitable or not, his mind went on as before,—working, scheming, and speculating.  Thus, at different times in the course of his correspondence with Small, who was a man of a like ingenious turn of mind, we find him communicating various new things, "gimcracks," as he termed them, which he had contrived.

    He was equally ready to contrive a cure for smoky chimneys, a canal sluice for economising water, a method of determining "the force necessary to dredge up a cubic foot of mud from any given depth of water," and a means of "clearing the observed distance of the moon from any given star of the effects of refraction and parallax"; illustrating his views by rapid but graphic designs embodied in the text of his letters to Small and other correspondents.

    One of his minor inventions was a new method of readily measuring distances by means of a telescope. [p.116]  At the same time he was occupied in making experiments on kaolin, with the intention of introducing the manufacture of porcelain in the pottery work on the Broomielaw, of which he was a partner.  He was also concerned with Dr. Black and Dr. Roebuck in pursuing experiments with the view of decomposing sea-salt by lime, and thereby obtaining alkali for purposes of commerce.  A patent for the process was taken out by Dr. Roebuck, but eventually proved a failure, like most of his other projects.  We also find Watt inventing a muffling furnace for melting metals, and sending the drawings to Mr. Boulton at Birmingham for trial.

    At other times he was occupied with Chaillet, the Swiss dyer, experimenting on various chemical substances; corresponding with Dr. Black as to the new fluoric or spar acid; and at another time making experiments to ascertain the heats at which water boils at every inch of mercury from vacuum to air.  Later we find him inventing a prismatic micrometer for measuring distances, which he described in considerable detail in his letters to Small. [p.117]  At the same time he was busy inventing and constructing a new surveying quadrant by reflection, and making improvements in barometers and hygrometers.  "I should like to know," he wrote to Small, "the principles of your barometer; De Luc's hygrometer is nonsense.  Probavi." Another of his contrivances was his dividing screw, for dividing an inch accurately into 1,000 equal parts.  He states that he found this screw exceedingly useful, as it saved him much needless compass-work, and, moreover, enabled him to divide lines into the ordinates of any curve whatsoever.

    Such were the multifarious pursuits in which this indefatigable student and enquirer was engaged; all tending to cultivate his mind and advance his education, but comparatively unproductive as regarded his pecuniary returns.  So unfortunate, indeed, had Watt's speculations proved, that his friend Dr. Hutton, of Edinburgh, addressed to him a New Year's Day letter, with the object of dissuading him from proceeding further with his unprofitable, brain-distressing work.  "A happy new year to you!" said Hutton; "may it be fertile to you in lucky events, but no new inventions!"  He went on to say that invention was only for those who live by the public, and those who from pride chose to leave a legacy to the public.  It was not a thing likely to be well paid for, under a system where the rule was, to be the best paid for the work that was easiest done.  It was of no use, however, telling Watt that he must not invent.  One might as well have told Burns that he was not to sing because it would not pay, or Wilkie that he was not to paint, or Hutton himself that he was not to think and speculate as to the hidden operations of nature.  To invent was the natural and habitual operation of Watt's intellect, and he could not restrain it.

    Watt had already been too long occupied with this profitless work: his money was all gone; he was in debt; and it behoved him to turn to some other employment by which he might provide for the indispensable wants of his family.  Having now given up the instrument-making business, he confined himself almost entirely to surveying.  Amongst his earliest surveys was one of a coal canal from Monkland to Glasgow, in 1769; and the Act authorising its construction was obtained in the following year.  Watt was invited to superintend the execution of the works, and he had accordingly to elect whether he would go on with the engine experiments, the event of which was doubtful, or embrace an honourable and perhaps profitable employment, attended with much less risk and uncertainty.  His necessities decided him.   "I had," he said, "a wife and children, and saw myself growing grey without having any settled way of providing for them."  He accordingly accepted the appointment offered him by the directors of the canal, and undertook to superintend the construction of the works at a salary of £200 a year.  At the same time he determined not to drop the engine, but to proceed with it at such leisure moments as he could command.

    The Monkland Canal was a small concern, and Watt had to undertake a variety of duties.  He acted at the same time as surveyor, superintendent, engineer, and treasurer, assisted only by a clerk.  But the appointment proved useful to him.  The salary he earned placed his family above want, and the out-doors life he was required to lead improved his health and spirits.  After a few months he wrote Dr. Small that he found himself more strong, more resolute, less lazy, and less confused than when he began the occupation.  His pecuniary affairs were also more promising.  "Supposing the engine to stand good for itself," he said, "I am able to pay all my debts and some little thing more, so that I hope in time to be on a par with the world."

    But there was a dark side to the picture.  His occupation exposed him to fatigue, vexation, hunger, wet, and cold.  Then the quiet and secluded habits of his early life did not fit him for the out-door work of the engineer.  He was timid and reserved, and had nothing of the navvy in his nature.  He had neither the roughness of tongue nor stiffness of back to enable him to deal with rude butty gangs.  He was nervously fearful lest his want of practical experience should betray him into scrapes, and lead to impositions on the part of his workmen.  He hated higgling, and declared that he would rather "face a loaded cannon than settle an account or make a bargain."  He had been "cheated," he said, "by undertakers, and was unlucky enough to know it."

    Watt continued to act as engineer for the Monkland Canal Company for about a year and a half, during which he was employed in other engineering works.  Among these was a survey of the River Clyde, with a view to the improvement of the navigation.  Watt sent in his report; but no steps were taken to carry out his suggestions until several years later, when the beginning was made of a series of improvements, which have resulted in the conversion of the Clyde from a pleasant trouting and salmon stream into one of the busiest navigable highways in the world.

    Among Watt's other labours about the same period may be mentioned his survey of a canal between Perth and Cupar Angus, through Strathmore; of the Crinan Canal, afterwards carried out by Rennie; and other projects in the western highlands.  The Strathmore Canal survey was conducted at the instance of the Commissioners of Forfeited Estates.  It was forty miles long, through a very rough country.  Watt set out to make it in September, 1770, and was accompanied by snowstorms during almost the entire survey. He suffered severely from the cold: the winds swept down from the Grampians with fury, and chilled him to the bone. The making of this survey occupied him forty-three days, and the remuneration he received for it was only eighty pounds, which included expenses.

    The small pay of engineers at that time may be further illustrated by the fee paid him in the same year for supplying the magistrates of Hamilton with a design for the proposed new bridge over the Clyde at that town.  It was originally intended to employ Mr. Smeaton; but as his charge was ten pounds, which was thought too high, Watt was employed in his stead.  After the Act of 1770 had been obtained, the Burgh minutes record that Baillie Naismith was appointed to proceed to Glasgow to see Mr. Watt on the subject of a design, and his charge being only £7. 7s., he was requested to supply it accordingly.  "I have lately," wrote Watt to Small, "made a plan and estimate of a bridge over our River Clyde, eight miles above this: it is to be of five arches and 220 feet waterway, founded upon piles on a muddy bottom."  The bridge, after Watt's plan, was begun in 1771, but it was not finished until 1780.

    About the same time Watt prepared plans of docks and piers at Port Glasgow, and of a new harbour at Ayr.  The Port Glasgow works were carried out, but those at Ayr were postponed.  When Rennie came to examine the design for the improvement of the Ayr navigation, of which the new harbour formed part, he took objections to it, principally because of the parallelism of the piers, and another plan was eventually adopted.  Watt's principal engineering job, and the last of the kind on which he was engaged in Scotland, was a survey of the Caledonian Canal, long afterwards carried out by Telford.  The survey was made in the autumn of 1773, through a country without roads.  "An incessant rain," said he, "kept me for three days as wet as water could make me; I could hardly preserve my journal book."

    In the midst of this dreary work Watt was summoned to Glasgow by the intelligence which reached him of the illness of his wife; and when he reached home he found that she had died in childbed. [p.123]  Of all the heavy blows he had suffered, he felt this to be the worst.  His wife had struggled with him through poverty.  She had often cheered his fainting spirit when borne down by doubt, perplexity and disappointment; and now she had died, without being able to share in his good fortune as she had shared his adversity.  For some time after, when about to enter his humble dwelling, he would pause on the threshold, unable to summon courage to enter the room where he was never more to meet "the comfort of his life."  "Yet this misfortune," he wrote to Small, "might have fallen upon me when I had less ability to bear it, and my poor children might have been left suppliants to the mercy of the wide world."

    Watt tried to forget his sorrow, as was his custom, in increased application to work, though the recovery of the elasticity of his mind was in a measure beyond the power of his will.  There were at that time very few bright spots in his life.  A combination of unfortunate circumstances threatened to overwhelm him.  No further progress had yet been made with his steam-engine, which indeed he almost cursed as the cause of his misfortunes.  Dr. Roebuck's embarrassments had reached their climax.  He had fought against the water which drowned his coal until he could fight no more, and he was at last delivered into the hands of his creditors a ruined man.  "My heart bleeds for him," said Watt, "but I can do nothing to help him.  I have stuck by him, indeed, till I have hurt myself."

    But the darkest hour is nearest the dawn.  Watt had passed through a long night, and a gleam of sunshine at last beamed upon him.  Matthew Boulton, of Birmingham, was about to take up the invention on which Watt had expended so many of the best years of his life; and the turning-point in Watt's fortunes had at last arrived.

 


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