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mere drudgery of physical life ; and the Wealth of Nations" appeared to regenerate the one, and steam was directly applied to effect the other.

The present writer has no special information either on steam or steam-engines to place at the disposal of his readers. Precisely the reverse. Though he has read attentively and minutely, and whensoever chance offered, has observed the various mechanical appliances by which steam has been made subservient to the comfort, necessity, or luxury of man, he has never had-or, rather, has never embraced—the opportunity of making a special study of the steam-engine. He has his reading and thought, but neither his own experience, nor analogies derived from it, to guide him in this exposition; and though he has sought the best authorities open to him, he fears that in a subject so alien to the usual habits of his life, so far apart from his own specialities, so entirely derived from bookknowledge, and so untested by aught except reference to the worksnot perhaps always thoroughly comprehended-of the chief writers on steam and its applications, he may neither be able to do justice to his theme nor his own ideas. He essays with humility, therefore, the following exposition as the most concise and explicit he can produce of the combined results of reading and reflection regarding the practicalization of steam and steam-power.

Man's progress in the utilization of steam seems to have been very slow. Hero of Alexandria (cir. 120 B.C.), in a work “On Pneumatics,” describes two machines of his own invention, in which a rotary motion was conveyed in the one case by the emission of heated air, and in the other by the immission and emission of steam. The latter is the first known attempt to effect the production of motion by the employment of elastic vapour. It was, however, used only as a philosophical toy, and does not seem to have been applied to any merely utilitarian purpose. This plaything is the original of that distinguished species” of mechanism now known as the steam-engine. It was for ages looked upon as a curiosity of mechanics. Nor till the stir and ferment of the Reformation had given men the belief that nothing was impossible, does it appear to have entered into the human mind that the spirals of vapour rising from heated water could become weariless labourers for humanity; and then it was more an outburst of rhetoric than a scientific appraisement of facts. A volume of sermons by Mathesius, published at Sarepta in 1563, contains a suggestion of such a possibility. About thirty years thereafter, the Alexandrian toy was taken as a model for a mechanical turnspit. Baptista Porta in Italy, and David Rivault in France, occupied themselves, as students of the powers, qualities, uses, &c., of steam. Indeed, the need of some new industrial energy appears in the early part of the 17th century to have been simultaneously suggested to several minds. Hence originated the many experiments on heat, air, gases, motion, &c., which are recalled to us by the mere mention of the names of Galileo, Descartes, Torricelli, Wallis, Roëmer, and Leibnitz; Stevinus, Newton, Castelli

, and Guericke; De Caus, the Marquis of Worcester, Huygens, and Boyle.

A century of tentative approaches were made to the solution of the question, each supplying some preliminary to its successful accomplishment, none effecting the required result. The knowledge of the qualities and properties of the materials was requisite before contrivance could efficiently act and superadd to nature such appli. ances as would fit in with her divinely ordained activities, and cause the ordinary action of the elements involved to achieve a human purpose in harmony with the ever-abiding designs of THE ONE. For this is the great law of discovery-to bring human conceptions into harmony with the Divine plan; and whensoever that is accomplished, the means of touching to their required uses the ordinary elements of nature become self-evident. The science of dynamics might almost be said to have had its origin in the desire to know the laws of force. The Bernouillis, Varignon, Herman, Euler, Segner, and Boscovich, are the chief names to which the scientific correlation of statics and dynamics may be traced. And though the names of Newton, D'Alembert, Venturi, Deluc, &c., may not be omitted from a catalogue of the assistants in the discovery of the true theory of the steam-engine, this distinction belongs, perhaps, more justly to the originators of and active agents in arranging a true theory of heat. Without neglecting to notice the efforts of the Florentine academicians, we may mention the thermometers of Fahrenheit and Reaumur as tending much to the consolidation of this science. But perhaps the greatest achievements in the investigation of the theory of heat were made by Drs. Cullen and Black, professors in the Glasgow University, the latter of whom was a patron of the obscure though ingenious mechanician by whom steam was first utilized. Dr. Black expounded the theory of latent heat; Scheele introduced the idea of the radiation of caloric: and all these various efforts combined led to the successful and systematic application of the laws of heat to the furtherance of the mechanical arts, and ultimately to the actual construction of the most marvellous and multiform mechanism of modern days -the steam-engine.

Sir Samuel Morland, master of mechanics to the King of England, made some experiments upon the elasticity of steam before 1682, and projected a scheme for raising water by the force it afforded. Dr. Denys Papin, a native of Blois, who had assisted Boyle in many of his experiments, and who had thus his attention directed to the grand mechanical problem of that time, published in the Acta Eruditorum of Leipsic, in 1685, several communications, which show that he had attained a clear idea of the nature of the material facts upon which the construction of a steam-engine depended, and shortly afterwards made some steps towards the construction of such a mechanism. Steam was now well known to 'be capable of acting as a motive power; the proper applicability of its force to useful purposes was the great difficulty. To Papin we owe the invention of the digester and the safety valve. Captain T. Savery, about 1698, invented an engine, in which steam was employed to give a force for the draining of mines or fens, the propulsion of water through mansions and palaces, and pumping it from ships. Amontons, in 1699, proposed a fire-wheel; but this, though ingenious in conception, was liable to many derangements, and was found impracticable.

Dr. André Dalesme, in 1705, exhibited at Paris an engine for raising water by the force of steam; and Leibnitz, after examining Savery's mechanisms in England, sent a sketch of one of them to Papin, who renewed his attempts to make an effective working engine. Upon the basis of Savery's machine, Thomas Newcomen and John Cawley, the former a blacksmith, and the latter a glazier in Dartmouth, constructed an engine upon Papin's principle of a piston and a condensing process, using, however, Savery's mode of creating a vacuum by cold affusion, for whicb they were led by an accident to substitute the method of throwing a jet or stream of cold water into the cylinder. Further improvements were made upon this engine by Desaguliers, Henry Beighton, of Newcastleon-Tyne, John Smeaton, and others, but none of these engines employed the direct force of steam as their motive power, and none of the improvers made any alteration in or advance upon the principles of steam mechanism. These engines, therefore, have been designated, for distinction's sake, atmospheric steam engines. All the elements of a successful adaptation of steam to industrial purposes might now be said to have been gathered together, but, like the dry bones in Ezekiel's vision, they required a Divine breath to give them the life of usefulness. At length came the hour, and with the hour

“The master hand
That seized the fire-flame, like Prometheus old,
And, out the black sbaft, through the grassy land,
Dragged up the iron from earth's rocky hold,
And gave command to both. Ye shall not rest
Till striving man is from work's bondage free.
Go, steam, and do man's hest; from east to west,

Ye wheels of iron, at his bidding flee." The following résumé of the chief steps through which the inven. tion had by this time passed will be found not only intelligible and interesting, but authoritative. “S. de Caus made steam act to raise water; Worcester performed this operation in a more regular and mechanical manner; Papin used the condensation of steam, and, through that, the atmospheric pressure, as well as the direct expansive force, and he worked the engine by a piston ; Savery condensed by refrigeration, instead of the mere absence of fire, but did not use the atmosphere; Newcomen used the jet for condensing, and the atmosphere for pressure, but did not use the direct force of steam; Desaguliers introduced the safety-valve ; Beighton and Smeaton improved the mechanism ; Dalesme needs not to be mentioned, as we are not informed what plan he executed, but he certainly made no step himself. If the direct force of steam, as well as atmospheric pressure, had been both employed, with the jet of cold water, the safety-valve, and the contrivance for regulating the supply valves, a far better engine than any ever known before the time of Watt would have been produced, and yet nothing whatever would have been added to the former inventions, they would only have been combined together. The result of the whole is, that one of the greatest theoretical steps " was made by Papin, who was, during a long period, little commemorated; and that Savery and Newcomen, who have been by many called the inventors, were the first of all the ingenious and useful persons whose successive improvements we have now recorded, to apply the steam engine to practical purposes. France has thus produced the man who, next to Watt, may be regarded as the author of the steamengine; of all Watt's predecessors, Papin stands incontestably at the head; but it is almost certain that he never actually constructed an engine. Though the engine of Savery was of considerable use in pumping to a small height, and indeed has not entirely gone out of use in our own times; and though Newcomen's was still more extensively useful, from being applicable to mines, not only had no means ever been found of using the steam power for any other purpose than drawing up water, but even in that operation it was exceedingly imperfect and very expensive, insomuch that a water power was often preferred to it, and even a horse-power, in many cases, afforded equal advantages. The great consumption of fuel which it required was its cardinal defect; the other imperfection was its loss of all direct benefit from the expansive force of the steam itself. That element was only used in creating a vacuum, and an air-pump might have done as much, had it been worked by water or by horses. It was, in the strictest sense of the word, an air and not a steam-engine.”* When the progress of invention had proceeded thus far, “ the genius of Watt, guided by sound judgment, and urged by unremitting application, effected in less than forty years a complete change in the power of mechanism;" and hence we now devote our efforts to a brief abstract of the life and doings of the utilizer of steam-James Watt.

In a small, comfortable cottage at the east end of the south side of Dalrymple Street, in the old burgh town and seaport of Greenock -of the Council of which he was treasurer-dwelt Mr. James Watt, shipwright, builder, and general merchant, a clever pursuer of many handicraft arts, and a successful conductor of such commercial speculations as the state of trade at that time afforded opportunity for. His wife was Agnes Muirhead, a handsome, well-informed, and good-tempered woman, in whose veins ran the “ bluid” of the “: lairds of Lachop.” To this honest pair there were born five children, of whom three, two sons and a daughter, died in infancy,

* Lord Brougham's works, vol. I., Lives of the Philosophers of the Time of George III., article, Watt, p. 30.

and the latest born, John, was logt at sea in the twenty-fourth year of his age-only seven years after the death of his mother, in 1755. Their fourth child was the James Watt to whom

"Nature disclosed the artful plan

To mould the inist into Leviathan." He was born 19th Jan., 1736. He was sickly in childhood, and was an object of much anxiety, for the parents, tried by former losses, almost despaired of training him through the perils of boy hood, or of his ever attaining to man's estate. The delicate boy, though kept long from school, was of an observative and thoughtful turn of mind, and found in the shop and workshops of his father, as well as in the splendid scenery of land-locked sea and towering mountain near him, multitudes of " object lessons,” which excited his intelligence, guickened his aptitudes, and, by gratifying, his curiosity, increased his thirst for information. He made teachers of all he saw, and often made himself master of their secrets. His mother taught him to read, his father imparted to him the rudiments of writing and arithmetic. He was carefully drilled in his lessons, though not harassed with them, and though far outstripped in schoollearning by many of the burly youngsters who jibed the feeble home-pet, he had an education of the feelings and senses seldom acquired in those old days of stern catechetical discipline and classical drudgery. Marvellous stories are often told of "the boyhood of great men,” as if, in their early years, their future eminence had been foreshadowed. In the biography of James Watt these are not wanting; nor do we think that they are, in this case, apocryphal. It would be impossible for us, however, in a mere sketch, such as this must be, to criticize minutely the tales of his selfsuggested discovery of geometrical truths, of his early acquaintance with algebraic formulæ, of his precocious powers of calculation, and of inventing and constructing philosophical toys. It must suffice us to say that such stories seem to be authentically narrated, and appear to be credible, for the boyhood of Watt was different in its conditions from that of the majority of children in his day.

After the anxious expenditure of a mother's care, and the faithful patience of a father's affection, the boy's health seemed to warrant his attendance at a public school, there to be braced by competition, and fired by contact with his age-fellows. In the commercial school of Mr. McAdam he increased his knowledge of penmanship and accounts, under the learned and excellent Robert Arrol, Master of the Burgh Grammar School of Greenock; he acquired a fair acquaintance with Latin, and a “ little Greek ;" while with a relative of his own, John Marr, he studied mathematics with zeal and purpose, with a loving diligence which won his master's and his parents' admiration. Though not a frequent companion in the giddy joys of schoolboy life, he was a great favourite with his comrades, on account of his mechanical ingenuity, and his rare power of storytelling,--a power which he exercised with an imaginative fertility

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