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“ some ideas which it was thought might prove useful, and “ be deserving of the outlay requisite for experiments on a
large scale. His notion is, that the force of the steam which “ rises from boiling water might be employed as a moving
power: he has shown by a machine in which that force “ alone made water spout to a great height, how powerful it “ is.” M. Prony suggests that M. Dalesme's model might still be found to exist in the collection of machines belonging to the Academy; but it seems never to have made its appearance again. The effect described might evidently have been produced by something not more deserving the name of a machine than the hollow ball and tube of De Caus.
The improvements of Smeaton on Newcomen's, or the atmospheric engine, (as it was called from the pressure of the atmosphere on the piston being the moving power in the downward stroke), are the last to which we are here called on to allude before entering on the consideration of those of Watt. In getting engines erected, Smeaton was so much baffled and annoyed by the irregularity and insufficiency of their work, arising often from the bad proportions of their parts, that he constructed a small experimental engine, not above four horses' power, from which he deduced a valuable table of the proportions of the parts and of their relative performance; the experiments are said to have been made about the year 1765, although Smeaton did not proceed to build large engines in accordance with the results obtained, till nine years afterwards; soon after which he designed several, some of them of more than a hundred horse power, in which it was admitted that there was a considerable saving of fuel,-equal in some cases to one-third of the previous consumption. But those were not in existence at the period of Watt's life to which we must now attend ; and even the table we have spoken of was not published by its author, but was found after his death among his papers, now in the possession of the Royal Society.
HIS HISTORY –CARRON IRON-WORKS
INTRODUCTION TO MR. WATT - PROGRESS OF THE NEW STEAM-ENGINE TESTUDO BOILER DIFFICULTIES WITII CYLINDER AND PISTON - PLATECONDENSER CIRCULAR STEAM-ENGINE OR STEAM-WHEEL DR. ROEBUCK'S EMBARRASSMENTS - MR. WATT'S LAND-SURVEYING AND CIVILENGINEERING -HIS VISIT TO SOHO INTRODUCTION TO DR. SMALL RENEWED EXPERIMENTS PROPOSALS OF PARTNERSHIP WITH MR. BOULTON - PATENT OF 1769.
FROM the narratives of both Dr. Black and Dr. Robison, it is apparent that, next to the inventor himself, the person at first most deeply interested in the mechanical and commercial success of the invention, the origin of which has now been so fully detailed, was Dr. Roebuck, an ingenious and enterprising man, whose ultimate want of success in life ill rewarded his fondness for practical science, and his energetic exercise of very considerable talents and industry. It seems indeed a singular fatality, that even his early connection with the greatest invention of his age, full of future profit as it promised to be, and narrowly as we now see that it failed to realise that hope to him, was not only of no ultimate service to his own fortunes, but had nearly cut short the progress of the invention itself; which was long submerged, and wellnigh altogether lost, in the financial wreck in which his affairs became involved.
For the best account of the life and pursuits of the gentleman who was thus destined to become the temporary though unsuccessful associate of Mr. Watt in his important scheme, the public are indebted to the pen of the late venerable Professor Jardine, of Glasgow College. From a biographical notice which he communicated to the Royal Society of Edinburgh, and which is published in their Transactions,* we find
* • Trans. R. S. E.,' iv. p. 65, 1796.
that Dr. Roebuck, who was born at Sheffield in 1718, and received some of his early education under the care of Doddridge and in companionship with Akenside, studied medicine at the University of Edinburgh, and formed there an intimate acquaintance with Hume, Robertson, and others of their eminent contemporaries. Graduating at Leyden, on his return to England he settled as a practising physician at Birmingham, where he rapidly rose into extensive and lucrative employment, and was at the same time enabled to gratify his inquiring habit of mind by numerous scientific researches, in which he engaged with ardour. The study of chemistry, one of his favourite pursuits, he now prosecuted practically, with great ingenuity and perseverance; inventing improved and economical processes for refining and working gold and silver, as well as for manufacturing many other substances commonly used in the arts; and, in conjunction with Mr. Samuel Garbett, establishing a large laboratory, where his various processes were profitably carried out on a very extensive scale. Sulphuric acid, which had previously been made, at great expense, in glass retorts, they succeeded, after many experiments, in preparing, by means of leaden vessels, at less than a fourth of its former cost; and on their establishing a manufactory of it at Preston Pans, in East Lothian, the consumption of the article increased enormously, and the profits of their undertaking became proportionally large.
Emboldened by this success, Dr. Roebuck proceeded to carry out a work of far greater extent and importance, which both in a private and in a national point of view has more than equalled the sanguine expectations then formed of its probable utility. Among the numerous subjects to which he had turned his attention, was the smelting of iron-ore; a process which, as then commonly conducted, was capable, he had satisfied himself, of very great improvement. Having, with his partner Mr. Garbett, now realised some fortune by the profits on his other processes, and being easily enabled, by the confidence reposed in his skill and judgment, to obtain the loan of the further capital that was necessary, he resolved to establish in Scotland a manufactory of iron on a great
scale. To him was left not only the direction of all that concerned the buildings, machinery, and processes of the manufacture, but, in the first place, the selection of a proper site for the intended works; and on the banks of the river Carron, in Stirlingshire, he found united every natural facility for his purpose. In that situation, with great waterpower, were combined the advantages of ready transport by -sea, and supplies, in the immediate neighbourhood, of excellent iron-ore, limestone, and coal,-minerals which, after the lapse of a century, have in that district shown no signs of exhaustion.
The Carron iron-works, in their original state, were completed by the end of 1759, and the first furnace was blown on the 1st of January, 1760. Dr. Roebuck then lived at the house of Kinneil, near Borrowstoness, a “very ancient and
very stately” mansion,* about three miles from Linlithgow, the rural beauties of which were, half-a-century later, thus described by the poet Campbell, while there on a visit to his venerable friend Dugald Stewart :-“Stewart's residence is
old chateau of the Dukes of Hamilton, agreeably situated near the sea, opposite the classic Ben-Ledi, and surrounded
by fine groves that resound with the songs of birds, the “ cawing of rooks, and the sweeter cooing of wood-pigeons. “ The whole scene, with the society and conversation of my “ friends, sinks deep into my mind." +
In planning the Carron machinery, Dr. Roebuck availed himself of the great talents of Mr. Smeaton, who has been justly termed the father of civil-engineering in Great Britain, and who, having in 1750 begun business in London as a philosophical-instrument-maker, was already fast rising to eminence in both of those professions. He had not, however, been previously brought into notice in Scotland; and the introduction of his skill into that country, in which he afterwards directed many important engineering operations, is one of the numerous proofs of Dr. Roebuck's observant and
Sir David Wilkie ; see his Life' by Allan Cunningham, vol. i., p. 461.
+ Beattie's Life of Thomas Camp• bell,' vol. ii. p. 286.
penetrating judgment. Among Mr. Smeaton's Reports, which were published by the Society of Civil Engineers,* and form an interesting memorial of his labours, are included several that were addressed to the Carron Company, concerning the supply and regulation of the water-power, the construction of blowing-machines on improved principles, of mills for boring the great guns known in the British Navy as carronades,f and other kindred matters.
The works established under such advantageous circumstances, and directed by such able advice, did not fail to prosper; and they proved a lucrative investment of the means of their principal projector, as well as of his associated friends. Well had it been for all of them had his attention continued to be engrossed by the profitable manufacture which he had thus so energetically created; but, as the various processes were gradually reduced to little more than mere routine, his ardent mind sought fresh scope for exertion, and he embarked in an adventure, which, although at first it had a semblance of further utility and profit, ended in involving his friends in grievous embarrassment, and himself in irretrievable pecuniary ruin.
One of the great principles of the improved method of manufacturing iron, as practised at Carron, was the use of pitcoal instead of charcoal; which, although it had
* In three volumes, quarto, 1812 ; “ effects, when tried against timber, which were followed, in 1814, by a “ induced its ingenious inventor to fourth volume of his Miscellaneous “ give it the name of smasher.” The Papers, comprising all of his com- new gun soon got the name of carmunications to the Royal Society, ronade, and those of the larger calibres printed in the ‘Philosophical Transac- were found to be so formidable from tions.'
the force and weight of their shot, † “ In the early part of 1779,” says (from 32 to 68-pounders), that within Mr. James, in his well-known and
a very few years of the date of their admirable • Naval History,' "a piece of invention they were introduced into “ carriage-ordnance, the invention, by almost every ship in the British navy; * all accounts, of the late scientific while a carronade of smaller calibre, "General Robert Melville, was cast (24 down to 12-pounders), was in 1795 “ for the first time, at the iron-works ordered to be supplied to the launch " of the Carron Company, situated on of every ship of the size of an 18-gun " the banks of the river Carron, in brig or above it, to aid in the service " Scotland. Although shorter than of cutting out vessels from the enemy's " the navy 4-pounder, and lighter, by harbours.—See • The Naval History " a trifle, than the navy 12-pounder, of Great Britain,' by William James, " this gun equalled in its cylinder the vol. i. pp. 47 and 436, ed. 1826. " 8-inch howitzer. Its destructive