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the chief of the railway department, and who | and the irregularity of motion, when once had been commissioned to inquire into the evolved, tends by the natural relation of the means of ensuring safety in railway transit, several parts and actions, to cause or to inwe find the sources of danger thus indicated : crease every other variety of eccentric force,

“On analyzing the strain upon the axles The improvement, if such be possible, which it was found to consist—first, of a vertical should throw the axle of the driving wheels strain, due either to the portion of the weight into revolution by some continuous and symof the engine bearing upon that point, in metrical impulse, will remove by far the consequence of the position of the centre of largest part of the sources of danger, and gravity, or to the action of the springs of the open wider limits to the possibility of greater hinder axles in the six-wheeled engines. speed. This strain being thus defined, even supposing In the process of weaving by the powerthat the parts upon which it acts are as near loom we find an analogous example of veas possible to the point d'appui formed by locity limited by the broken or alternating the wheels, it tends nevertheless to bend the motion of the acting forces. The rapidity axle in a vertical direction. Secondly, a ten- with which the shuttle can be thrown from sion arising from the conoidal form of the side to side between the threads of the warp, peripheries of the wheels, and inequalities in is limited by the strength of the woof-thread the inclination of the rails ; from which it it carries across. When the strain is so great happens that the peripheries of two wheels as to cause more than a certain average fixed upon one axle never touch the rails at number of breakings, the nett product of the the same point at the same time, and con- machine will be increased by working at a sequently each of the wheels will slip alter- lower velocity. By a recent improvement, nately upon the rails. If the twist resulting the shuttle is made at every vibration or therefrom is not too violent, it keeps all the “shot,” to commence its motion slowly and molecules in a constant state of vibration. and increase in velocity as it proceeds ; thus Thirdly, shocks arising from inequalities in diminishing the strain upon the thread, and the road caused by the undulations of the economizing time, even in the four or six feet rails at their points of junction, on the pas that constitute the average extent of each sage of a train. These shocks increase in

“shot.” And by this means the looms are violence in proportion to the speed, and act sometimes worked at a rate of 180 threads in a direction at right angles to the axis of per minute, or 3 in every second. This will the axle. Fourthly, a strain of another de constitute the absolute limit of speed, under scription, arising from the oscillations of the the existing form of construction. To excarriages, acts upon the axles both in the tend it we must introduce a new principle, direction of their length and at right angles and discover some method of weaving the thereto; increasing in force in proportion to tissue in a cylindrical web; when the oscilthe diameter of the wheels.”

lation of the shuttle might be transformed Some of the dislocating forces here de- into a continuous revolution, and the strain scribed increase as stated, in direct proportion upon the woof, arising from the perpetual to the increase of velocity; others in a much stoppage and change of motion, be annihihigher ratio. The great cause of disturbance lated. may be traced to the mode in which the ex The history of the first invention of the pansive power of the steam is transmitted, power-loom contains a curious proof, how through the axle, to the driving wheels, by much more difficult is the discovery of any means of a pair of piston-rods working upon absolutely new principle, by which the old cranks in the axle, and placed upon opposite forms and processes of manipulation are ensides of the line passing through the centre tirely superseded, than the mere contrivance of gravity. Of necessity the two cranks can of means to imitate by machinery what has not lie in the same plane, but must form a been already done by hand. The latter reright angle with one another. Their forces, quires only a very common endowment of therefore, can never be in counterpoise. the inventive faculty; the former demands While the right-hand piston is at its dead the presence of creative genius. More than point, the left-hand will be at a maximum; a hundred years before the invention of the and while the axle is pushed forward on one steam-loom, in the Philosophical Transacside, it is pulled back on the other; and these tions for August, 1678, there was given some interchanges of impulse, when at high speed, account of “a new engine to make woolen recur several times in every second. Enor- cloths without the help of an artificer”mous tendency to oscillation is thus produced, I being a communication from a M. de Gennes,

“an officer belonging to the sea.” Much in- first appear so hopelessly superior. The genuity is exhibited in the mechanical con- hand-loom weavers found themselves able to struction of this engine,' considering the live in the race" with the steam-engine, altime when it was produced; but in those though at a terrible sacrifice. The compedays the only method of passing the woof- tition has been persevered in, with melancholy thread through the warp, was by the fingers pertinacity, to the present day ; until society of the weaver, assisted occasionally by a

has the burden and the scandal of a numerous notched stick. And accordingly M. de class of individuals, industrious but ill-judgGennes, or whoever was the inventor of the ing, who have, even in good times, to batile machine, could hit upon no better plan than for a bare subsistence against fearful odds ; a complicated imitation of the human hand and who, in the frequently recurring periods and arm, by which his shuttle is carried from of depression, present the most afflicting side to side. Long afterwards, a common spectacles. weaver invented the “fly' shuttle, wbich is The machine maker, in his turn, will enshot to and fro by springs ; and modern in- deavor to frustrate the innovations that tend ventors, having the benefit of this capital to render his capital and experience, like the discovery, started from a high vantage- skill of the operative, in a great measure ground, and have succeeded in bringing the valueless. If some new power should be power-loom to its present state of excel discovered and trained to do for us more lence.

efficiently what steam does now, its adoption But the difficulty with which a novel idea would be impeded by all the improvements is caught or worked, is not the only one that in the steam-engine, which four generations stands in the way of the inventor. Improve of engineers have combined to perfect. The our mechanism as we may, the human ope- most proper proportions of size and strength; rator will always form an important element the simplest arrangement of parts; the best in our combinations; and will often prove by form and construction of every valve and far the most intractable of our materials. joint—even the machines that make the maOnce let the workman be inured to the rou- chines—have been long since ascertained and tine performance of duties on one machine, provided. The new power must be gifted and it becomes a work of much time and with advantages very great and undeniable, cost to transfer him to another. The dearly if it can supersede, in all the rudeness of its acquired skill which constituted his chief primitive condition, the elaborate perfection capital is rendered useless, and the appren- of the established engines. ticeship to his new tasks must be completed The common watch is in many of its parts at much labor to himself and expense to his a very ill-constructed machine. The train of employers. We are assured by high au wheel-work which transmits the motion of the thority that little short of a whole genera- main-spring, for example, is contrived on printion must expire, before the change can be ciples so faulty, that they would be scouted thoroughly established. When some of the by every practiced mechanician. Yet there more remarkable inventions, like that of can be no doubt that any attempt to introArkwright's spinning jenny, 'were first in- duce a better macbine would utterly fail, as troduced, it was found necessary to discard a commercial enterprise. Long used methods the whole of the trained operatives, and to and ingenious engines have been specially intrust the attendance upon the new ma- provided to fashion and cut every one of the chines either to young children, or to recruits minuter parts which go to compose the existdrawn from rustic neighborhoods, who had ing instrument. Mr. Dent, in a lecture never touched a spindle. It was no wonder delivered at the Royal Institution, stated that the “ skilled laborer” of the old system that every watch consisted of at least 20% denounced and resisted the new ; just as the pieces, employing probably 215 persons, disold English archer resisted the introduction tributed among 40 trades—to say nothing of of the musket, after having acquired by in the tool-makers for all these. If we were cessant practice from earliest childhood his now materially to alter the construction of the unerring skill as a marksman, and so great watch, all those trades would have to be remuscular power that he could be recognized learnt, new tools and wheel-cutting engines a mile off, merely from the size of his arms. to be devised, and the majority of the workThe spinning jenny, indeed, presented such men to begin life again. During this interval an enormous increase in speed and economy, the price of the new instrument would be that the old workers gave in without a strug. enormously enhanced.

We should again gle. But the weaving machines did not at I hear men speak, like Malvolio, of “winding

up their watches” as a token of their wealth., by new apparatus.

This ratio was of course Thus in our complicated state of society, temporary and accidental. Many of the large even machines in process of time come to manufacturers in Lancashire and the West surround themselves with a circle of “vested Riding find it worth their while to employ interests,” which embarrass all our attempts skillful mechanics at high salaries, for no at improvement.

other purpose than to suggest improvements Looking back on what we have written as in the machinery. The result is that their to the limits of improvement, we come to the factories contain specimens of contrivance conclusion that it is impossible to lay down surpassing any other in the world. Some of any general law upon the subject. Every the mechanism used in cotton printing, or in invention must be judged by its own merits, the “differential box” for supplying cotton and according to the special object in view. to the spinning frames, is beyond comparison Nine times out of ten, probably, the object superior in delicacy and ingenuity to the most will be nothing more than economy, in a re-complex movements of a chronometer. And duction of cost. In the tenth case, it may the human operative, in imitation and by the be for increased safety, simplicity, velocity, aid of the machine, acquires a perfection litor power.

But each case requires to be cal- tle less marvellous. The rapidity of his culated for itself; and some of the elements motion, the acuteness of his perception, renfor such calculations we have now endeavored der him a fitting companion for the intricate to give. These elements are sometimes sim- mechanism he employs. In astronomical ple enough; yet it is astonishing how often observations, the senses of the operator are they are overlooked. To give a familiar rendered so acute by habit, that he can estiillustration. The art of flying has more or mate differences of time to the tenth of a less occupied the inventive power of man, second; and adjust his measuring instrument since the days of Dædalus. Here we may to graduations of which 5000 occupy only allow that cost and even danger may be left an inch. It is the same throughout the comout of consideration, and that the question is monest processes of manufacture. A child one of simple practicability. The balloon of who fastens on the heads of pins will repeat fers the nearest approximation to a successful an operation requiring several distinct mosolution ; since, though we could not prop- tions of the muscles one hundred times a erly fly, we might float suspended to those minute for several successive hours. In a buoyant spheres; and efforts to steer balloons recent Manchester

paper, ,

it was stated that a have accordingly been innumerable. Now a peculiar sort of twist or “ gimp,” which cost very simple calculation will show that a wind three shillings making, when first introduced, of fifteen miles an hour would exert, upon was now manufactured for one penny; and any sphere of useful size, a pressure greater this not, as usually, the invention of a than the weight it could sustain in the air. new machine, but solely through the inThe power consequently which would be re- creased dexterity of the workman. quired to retain the machine stationary against To the inventive genius of her sons Engsuch a wind-or, what is the same thing, pro- land owes the foundation of her commercial pel it at a like rate througli a still atmos- greatness. We will not go the length of phere—must be greater than that which asserting that she retains her proud pre-eminwould keep it up in the air without a balloon ence solely upon the condition of keeping at all. A good three-fourths of prospective twenty years ahead of other nations in the aëronauts, therefore, surrounded their task practice of the mechanical arts; but there is with unnecessary difficulty. And the remain no question that a fearful proportion of our der, who devised so many varieties of imi- fellow-subjects hold their prosperity upon no tative plumage and pinions, might have saved other tenure. And quite independently of their labor if they had but reflected that, be- what may be done by our rivals in the markets fore they could use their ingenious apparatus, of the world, it is of vast importance to our inthey must possess some motive power which creasing population that the conquest over could support its own weight and something nature should proceed unchecked. Towards more, for a reasonable time. They were this object we have thought we might contriconstructing new wings, while the thing bute some slight assistance by indicating some wanted was a new steam-engine.

of the principles upon which the warfare In many branches of manufacture mechan- must be conducted, and the mental training ical improvement has been so rapid, that Mr. of those engaged in carrying it on. That Babbage estimated the average duration of there should be so little provision for this the machinery at only three years; by the training among our ordinary establishments expiration of which time it was superseded | for education, shows a neglect, at which, if

any anomaly of the sort could surprise us, the principle is once fairly studied, mechaniwe might well be surprised. With the ex cal inventions are simultaneously made in ception of the College at Putney, confined to many places at once. The honors of the a few aspirants to the honorary degree of C. electrotype processes, of the Daguerreotype, E.—for practically the profession is not limit- the electric telegraph, the screw-propeller, ed to such—the scientific education of the and a host besides, are disputed by a hundred young mechanist

must be self-acquired, rival claimants. Chance, we thus perceive, or, at best, irregularly obtained in the did not produce those discoveries ; and from classes voluntarily formed among the mem the same facts we obtain a gratifying assubers of literary institutions. Yet every day rance that it could not have prevented their the necessity for practical and technical production. Well directed education will instruction is becoming more manifest. We make the creations of the human mind more see it marked as strongly in the success of the abundant, as printing has already secured few who succeed, as in the failure of the their indestructibility. many efforts of ignorant and mistaken inge Of the legal aids or hindrances to invention, nuity.

it is not now our purpose to speak, although Blind intuition has now little hope of suc the anomalies of the laws in relation to the cess in the work of invention. Mere chance subject are confessedly flagrant. One sughas still less : it never, indeed, had so much gestion for improvement we have already as popular reputation gave it credit for. referred to. It is that every petitioner for a Chance might have set in motion the chande- patent should deposit in a gallery or museum, lier suspended in the Pisa cathedral ; but if accessible to the public, a working model, chance also suggested to Galileo the laws of drawing, or specimen of his invention, whether the pendulum, it must have belonged to that in mechanism, art, or manufacture. Musemultitudinous order of casualties, by which ums of this description would prove of infiideas are ordinarily propagated in fit and fer- nite assistance towards that scinentific educatile minds. Two generations ago Mr. Watt tion in which we are now so lamentably defiobserved, that he had known many workmen cient. The public would then obtain some who had suggested some improved adaptation countervailing advantage from a system, of of mechanism, but never one who invented which it is hard to say whether it is more an instrument, involving a principle, like that injurious by the monopoly that it confers or of his centrifugal " governor.' Machines that the privileges it denies; by the difficulties it do not involve a principle are now grown so imposes on an inventor who seeks to profit rare, that the range of invention is almost by his discovery, or by the hinderances wbich annihilated for the mere workman. On the it puts in the way of his successors, who have other hand, we observe how singularly, when i devised improvements on the first invention.

SALE OF HAYDON’S WORKS.

On Thursday a valuable collection of chalk | tured marble bust of General Washington, drawings, by the late unfortunate Haydon, and a large number of miscellaneous sketches. was disposed of by public auction at the Several virluosi were present. The bidding rooms of the Messrs. Robins, Covent Garden. was tolerably brisk, and, considering that the The collection consisted chiefly of sketches drawings were in a very crude and imperfect from the ancient masters, unfinished sketches state, the prices they realized were extremely of heads of his Royal Highness the Duke of good. Five finished heads of Lord Melbourne, Sussex, the late Mr. O'Connell, Lord J. Lord Stanley, Earl Grey, Lord Althorp, and Russell, and other eminent individuals. It Sir F. Buxton, were sold for 21. 7s. 6d. A also comprised the celebrated “sleeping head of Lord John Russell brought 21. 108. ; head,” exhibited at the British Gallery in and the “sleeping head” was sold for 57. 58. 1822, which is considered by the cognoscenti Several anatomical studies, presented by Sir to be one of the most exquisite specimens of David Wilkie to Haydon, were sold at resnative art; an unfinished gallery painting of pectable prices, but many of the sketches Uriel and Satan, upon which the artist was realized

very

small sums. The whole of the engaged until a short time previous to his proceeds will be devoted to the relief of the decease; a painting of Napoleon and hat for family of the lamented artist. the studio of Sir Robert Peel; a finely sculp

From Hogg's Instructor.

THE LATE JOHN STERLING.

BY GEORGE GILFILLAN.

Essays and Tales by John Sterling. Collected and edited, with a Memoir of his

Life, by Julius CHARLES HARE, Rector of Herstmonceux. London: Parker. 1848.

The removal of a young man of high per- remembered having speculated on points of formance and still higher promise is in all philosophy, and especially on the idea of circumstances melancholy. It is more so, if duty, which presented itself to him in this with the youth has expired either a new vein way—“If I could save my papa and mamma of poetry or a new view of truth ; and it is from being killed, I know I should at once do scarcely less so when the youth has been it. Now, why? To be killed would be very unconsciously the type of a large class of painful, and yet I should give my own concultivated and earnest minds, and when his sent to being killed.” The solution presented partial successes, baffled endeavors-his ad itself as “ a dim, awe-stricken feeling of unmitted struggles, and his premature fate- known obligation.” When about nine," he have been in some measure ricarious. was much struck by bis master's telling him

These three short and simple sentences that the word sincere was derived from the appear to us to include, positively and nega- practice of filling up flaws in furniture with tively, the essence of the late John Sterling, wax, whence sine cera came to mean pure, and shall form the leading heads in our after not vamped up.” This explanation, he said, remarks on his genius and character. He gave him great pleasure, and abode in his was, in the judgment of all who knew or had memory, as having first shown him that there carefully read him, a person of very distin- is a reason in words as well as in other things. guished abilities, and of still more singular When a boy, he read through the whole promise. He did no!, in our view of him, " Edinburgh Review,” of which his biographer exhibit indications of original insight or of says, “a diet than which hardly any could creative genius. But he has, from his pecu- yield less wholesome food for a young mind, liar circumstances, from his speculative and and which could scarcely fail to puff it up practical history, from his exquisitely-tuned with the wind of self-conceit.” We doubt the and swiftly-responsive symphonies with his validity of this dictum. We conceive that, age and its progressive minds, acquired a to a fresh elastic mind, the crossing of such double portion of interest and importance; varied territories of thought, the coming in his experience seems that of multitudes, and contact with so many vigorous minds, the in that final look of disappointed yet submis- acquiring such stores of miscellaneous inforsive inquiry which he casts up to heaven, he mation, the mere reading of such a mass of is but the foremost in a long, fluctuating, and masculine English, as the perusal of the enmotley file.

tire “ Edinburgh Review” implies, must have The external evidences of his powers and been beneficial, and tended to awaken curiosiacquirements are numerous and irresistible. ty, to kindle ambition, to stifle mannerism of In his boyhood he discovered striking tokens style, and, as the likely result of the many of a mind keen, sensitive, and turned in the severe criticisms in which the book abounds, direction of those high speculations from to allay instead of fanning the feeling of which his eye, till death, was never entirely self-conceit. Who but commends the indusdiverted. While barely eight," he distinctly try of the boy who reads all the English

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