Indeed many inventions appear to be coincident. A number of minds are working at the same time in the same track, with the object of supplying some want generally felt; and, guided by the same experience, they not unfrequently arrive at like results. It has sometimes happened that the inventors have been separated by great distances, so that piracy on the part of either was impossible. Thus Hadley and G.o.dfrey almost simultaneously invented the quadrant, the one in London, the other in Philadelphia; and the process of electrotyping was invented at the same time by Mr. Spencer, a working chemist at Liverpool, and by Professor Jacobi at St. Petersburg. The safety-lamp was a coincident invention, made about the same time by Sir Humphry Davy and George Stephenson; and perhaps a still more remarkable instance of a coincident discovery was that of the planet Neptune by Leverrier at Paris, and by Adams at Cambridge.
It is always difficult to apportion the due share of merit which belongs to mechanical inventors, who are accustomed to work upon each other"s hints and suggestions, as well as by their own experience.
Some idea of this difficulty may be formed from the fact that, in the course of our investigations as to the origin of the planing machine--one of the most useful of modern tools--we have found that it has been claimed on behalf of six inventors--Fox of Derby, Roberts of Manchester, Matthew Murray of Leeds, Spring of Aberdeen, Clement and George Rennie of London; and there may be other claimants of whom we have not yet heard. But most mechanical inventions are of a very composite character, and are led up to by the labour and the study of a long succession of workers. Thus Savary and Newcomen led up to Watt; Cugnot, Murdock, and Trevithick to the Stephensons; and Maudslay to Clement, Roberts, Nasmyth, Whitworth, and many more mechanical inventors. There is scarcely a process in the arts but has in like manner engaged mind after mind in bringing it to perfection. "There is nothing," says Mr. Hawkshaw, "really worth having that man has obtained, that has not been the result of a combined and gradual process of investigation. A gifted individual comes across some old footmark, stumbles on a chain of previous research and inquiry. He meets, for instance, with a machine, the result of much previous labour; he modifies it, pulls it to pieces, constructs and reconstructs it, and by further trial and experiment he arrives at the long sought-for result." [15]
But the making of the invention is not the sole difficulty. It is one thing to invent, said Sir Marc Brunel, and another thing to make the invention work. Thus when Watt, after long labour and study, had brought his invention to completion, he encountered an obstacle which has stood in the way of other inventors, and for a time prevented the introduction of their improvements, if not led to their being laid aside and abandoned. This was the circ.u.mstance that the machine projected was so much in advance of the mechanical capability of the age that it was with the greatest difficulty it could be executed.
When labouring upon his invention at Glasgow, Watt was baffled and thrown into despair by the clumsiness and incompetency of his workmen.
Writing to Dr. Roebuck on one occasion, he said, "You ask what is the princ.i.p.al hindrance in erecting engines? It is always the smith-work."
His first cylinder was made by a whitesmith, of hammered iron soldered together, but having used quicksilver to keep the cylinder air-tight, it dropped through the inequalities into the interior, and "played the devil with the solder." Yet, inefficient though the whitesmith was, Watt could ill spare him, and we find him writing to Dr. Roebuck almost in despair, saying, "My old white-iron man is dead!" feeling his loss to be almost irreparable. His next cylinder was cast and bored at Carron, but it was so untrue that it proved next to useless. The piston could not be kept steam tight, notwithstanding the various expedients which were adopted of stuffing it with paper, cork, putty, pasteboard, and old hat. Even after Watt had removed to Birmingham, and he had the a.s.sistance of Boulton"s best workmen, Smeaton expressed the opinion, when he saw the engine at work, that notwithstanding the excellence of the invention, it could never be brought into general use because of the difficulty of getting its various parts manufactured with sufficient precision. For a long time we find Watt, in his letters, complaining to his partner of the failure of his engines through "villainous bad workmanship." Sometimes the cylinders, when cast, were found to be more than an eighth of an inch wider at one end than the other; and under such circ.u.mstances it was impossible the engine could act with precision. Yet better work could not be had.
First-rate workmen in machinery did not as yet exist; they were only in process of education. Nearly everything had to be done by hand. The tools used were of a very imperfect kind. A few ill-constructed lathes, with some drills and boring-machines of a rude sort, const.i.tuted the princ.i.p.al furniture of the workshop. Years after, when Brunel invented his block-machines, considerable time elapsed before he could find competent mechanics to construct them, and even after they had been constructed he had equal difficulty in finding competent hands to work them.[16]
Watt endeavoured to remedy the defect by keeping certain sets of workmen to special cla.s.ses of work, allowing them to do nothing else.
Fathers were induced to bring up their sons at the same bench with themselves, and initiate them in the dexterity which they had acquired by experience; and at Soho it was not unusual for the same precise line of work to be followed by members of the same family for three generations. In this way as great a degree of accuracy of a mechanical kind was arrived at was practicable under the circ.u.mstances. But notwithstanding all this care, accuracy of fitting could not be secured so long as the manufacture of steam-engines was conducted mainly by hand. There was usually a considerable waste of steam, which the expedients of chewed paper and greased hat packed outside the piston were insufficient to remedy; and it was not until the invention of automatic machine-tools by the mechanical engineers about to be mentioned, that the manufacture of the steam-engine became a matter of comparative ease and certainty. Watt was compelled to rest satisfied with imperfect results, arising from imperfect workmanship. Thus, writing to Dr. Small respecting a cylinder 18 inches in diameter, he said, "at the worst place the long diameter exceeded the short by only three-eighths of an inch." How different from the state of things at this day, when a cylinder five feet wide will be rejected as a piece of imperfect workmanship if it be found to vary in any part more than the 80th part of an inch in diameter!
Not fifty years since it was a matter of the utmost difficulty to set an engine to work, and sometimes of equal difficulty to keep it going.
Though fitted by competent workmen, it often would not go at all. Then the foreman of the factory at which it was made was sent for, and he would almost live beside the engine for a month or more; and after easing her here and s.c.r.e.w.i.n.g her up there, putting in a new part and altering an old one, packing the piston and tightening the valves, the machine would at length begot to work.[17] Now the case is altogether different. The perfection of modern machine-tools is such that the utmost possible precision is secured, and the mechanical engineer can calculate on a degree of exact.i.tude that does not admit of a deviation beyond the thousandth part of an inch. When the powerful oscillating engines of the "Warrior" were put on board that ship, the parts, consisting of some five thousand separate pieces, were brought from the different workshops of the Messrs. Penn and Sons, where they had been made by workmen who knew not the places they were to occupy, and fitted together with such precision that so soon as the steam was raised and let into the cylinders, the immense machine began as if to breathe and move like a living creature, stretching its huge arms like a new-born giant, and then, after practising its strength a little and proving its soundness in body and limb, it started off with the power of above a thousand horses to try its strength in breasting the billows of the North Sea.
Such are among the triumphs of modern mechanical engineering, due in a great measure to the perfection of the tools by means of which all works in metal are now fashioned. These tools are themselves among the most striking results of the mechanical invention of the day. They are automata of the most perfect kind, rendering the engine and machine-maker in a great measure independent of inferior workmen. For the machine tools have no unsteady hand, are not careless nor clumsy, do not work by rule of thumb, and cannot make mistakes. They will repeat their operations a thousand times without tiring, or varying one hair"s breadth in their action; and will turn out, without complaining, any quant.i.ty of work, all of like accuracy and finish. Exercising as they do so remarkable an influence on the development of modern industry, we now propose, so far as the materials at our disposal will admit, to give an account of their princ.i.p.al inventors, beginning with the school of Bramah.
[1] 1 Samuel, ch. xiii. v. 21.
[2] State Papers, Dom. 1621, Vol. 88, No. 112.
[3] Lectures on the Results of the Great Exhibition of 1851, 2nd Series, 117.
[4] Dr. Kirwan, late President of the Royal Irish Academy, who had travelled much on the continent of Europe, used to relate, when speaking of the difficulty of introducing improvements in the arts and manufactures, and of the prejudices entertained for old practices, that, in Normandy, the farmers had been so long accustomed to the use of plough"s whose shares were made entirely of WOOD that they could not be prevailed on to make trial of those with IRON; that they considered them to be an idle and useless innovation on the long-established practices of their ancestors; and that they carried these prejudices so far as to force the government to issue an edict on the subject. And even to the last they were so obstinate in their attachment to ploughshares of wood that a tumultuous opposition was made to the enforcement of the edict, which for a short time threatened a rebellion in the province.--PARKES, Chemical Essays, 4th Ed. 473.
[5] EDOUARD FOURNIER, Vieux-Neuf, i. 339.
[6] Memoires de l" Academie des Sciences, 6 Feb. 1826.
[7] Farmer"s Magazine, 1817, No. ixxi. 291.
[8] Vieux-Neuf, i. 228; Inventa Nova-Antiqua, 742.
[9] Vieux-Neuf, i. 19. See also Inventa Nova-Antiqua, 803.
[10] Mr. Hallam, in his Introduction to the History of Europe, p.r.o.nounces the following remarkable eulogium on this extraordinary genius:--"If any doubt could be harboured, not only as to the right of Leonardo da Vinci to stand as "the first name of the fifteenth century, which is beyond all doubt, but as to his originality in so many discoveries, which probably no one man, especially in such circ.u.mstances, has ever made, it must be on an hypothesis not very untenable, that some parts of physical science had already attained a height which mere books do not record." "Unpublished MSS. by Leonardo contain discoveries and antic.i.p.ations of discoveries," says Mr. Hallam, "within the compa.s.s of a few pages, so as to strike us with something like the awe of preternatural knowledge."
[11] The plate is now to be seen at the Museum of Patents at South Kensington. In the account which has been published of the above discovery it is stated that "an old man of ninety (recently dead or still alive) recollected, or recollects, that Watt and others used to take portraits of people in a dark (?) room; and there is a letter extant of Sir William Beechey, begging the Lunar Society to desist from these experiments, as, were the process to succeed, it would ruin portrait-painting."
[12] "16th Oct. 1787. In the evening to M. Lomond, a very ingenious and inventive mechanic, who has made an improvement of the jenny for spinning cotton. Common machines are said to make too hard a thread for certain fabrics, but this forms it loose and spongy. In electricity he has made a remarkable discovery: you write two or three words on a paper; he takes it with him into a room, and turns a machine inclosed in a cylindrical case, at the top of which is an electrometer, a small fine pith ball; a wire connects with a similar cylinder and electrometer in a distant apartment; and his wife, by remarking the corresponding motions of the ball, writes down the words they indicate; from which it appears that he has formed an alphabet of motions. As the length of the wire makes no difference in the effect, a correspondence might be carried on at any distance: within and without a besieged town, for instance; or for a purpose much more worthy, and a thousand times more harmless, between two lovers prohibited or prevented from any better connexion. Whatever the use may be, the invention is beautiful."--Arthur Young"s Travels in France in 1787-8-9.
London, 1792, 4to. ed. p. 65.
[13] Mechanic"s Magazine, 4th Feb. 1859.
[14] A writer in the Monde says:--"The invention of postage-stamps is far from being so modern as is generally supposed. A postal regulation in France of the year 1653, which has recently come to light, gives notice of the creation of pre-paid tickets to be used for Paris instead of money payments. These tickets were to be dated and attached to the letter or wrapped round it, in such a manner that the postman could remove and retain them on delivering the missive. These franks were to be sold by the porters of the convents, prisons, colleges, and other public inst.i.tutions, at the price of one sou."
[15] Inaugural Address delivered before the Inst.i.tution of Civil Engineers, 14th Jan. 1862.
[16] BEAMISH"S Memoir of Sir I. M. Brunel, 79, 80.
[17] There was the same clumsiness in all kinds of mill-work before the introduction of machine-tools. We have heard of a piece of machinery of the old school, the wheels of which, when set to work, made such a clatter that the owner feared the engine would fall to pieces. The foreman who set it agoing, after working at it until he was almost in despair, at last gave it up, saving, "I think we had better leave the cogs to settle their differences with one another: they will grind themselves right in time!"
CHAPTER XI.
JOSEPH BRAMAH.
"The great Inventor is one who has walked forth upon the industrial world, not from universities, but from hovels; not as clad in silks and decked with honours, but as clad in fustian and grimed with soot and oil."--ISAAC TAYLOR, Ultimate Civilization.
The inventive faculty is so strong in some men that it may be said to amount to a pa.s.sion, and cannot be restrained. The saying that the poet is born, not made, applies with equal force to the inventor, who, though indebted like the other to culture and improved opportunities, nevertheless invents and goes on inventing mainly to gratify his own instinct. The inventor, however, is not a creator like the poet, but chiefly a finder-out. His power consists in a great measure in quick perception and accurate observation, and in seeing and foreseeing the effects of certain mechanical combinations. He must possess the gift of insight, as well as of manual dexterity, combined with the indispensable qualities of patience and perseverance,--for though baffled, as he often is, he must be ready to rise up again unconquered even in the moment of defeat. This is the stuff of which the greatest inventors have been made. The subject of the following memoir may not be ent.i.tled to take rank as a first-cla.s.s inventor, though he was a most prolific one; but, as the founder of a school from which proceeded some of the most distinguished mechanics of our time, he is ent.i.tled to a prominent place in this series of memoirs.
Joseph Bramah was born in 1748 at the village of Stainborough, near Barnsley in Yorkshire, where his father rented a small farm under Lord Strafford. Joseph was the eldest of five children, and was early destined to follow the plough. After receiving a small amount of education at the village school, he was set to work upon the farm.
From an early period he showed signs of constructive skill. When a mere boy, he occupied his leisure hours in making musical instruments, and he succeeded in executing some creditable pieces of work with very imperfect tools. A violin, which he made out of a solid block of wood, was long preserved as a curiosity. He was so fortunate as to make a friend of the village blacksmith, whose smithy he was in the practice of frequenting. The smith was an ingenious workman, and, having taken a liking for the boy, he made sundry tools for him out of old files and razor blades; and with these his fiddle and other pieces of work were mainly executed.
Joseph might have remained a ploughman for life, but for an accident which happened to his right ankle at the age of 16, which unfitted him for farm-work. While confined at home disabled he spent his time in carving and making things in wood; and then it occurred to him that, though he could not now be a ploughman, he might be a mechanic. When sufficiently recovered, he was accordingly put apprentice to one Allott, the village carpenter, under whom he soon became an expert workman. He could make ploughs, window-frames, or fiddles, with equal dexterity. He also made violoncellos, and was so fortunate as to sell one of his making for three guineas, which is still reckoned a good instrument. He doubtless felt within him the promptings of ambition, such as every good workman feels, and at all events entertained the desire of rising in his trade. When his time was out, he accordingly resolved to seek work in London, whither he made the journey on foot.
He soon found work at a cabinet-maker"s, and remained with him for some time, after which he set up business in a very small way on his own account. An accident which happened to him in the course of his daily work, again proved his helper, by affording him a degree of leisure which he at once proceeded to turn to some useful account. Part of his business consisted in putting up water-closets, after a method invented or improved by a Mr. Allen; but the article was still very imperfect; and Bramah had long resolved that if he could only secure some leisure for the purpose, he would contrive something that should supersede it altogether. A severe fall which occurred to him in the course of his business, and laid him up, though very much against his will, now afforded him the leisure which he desired, and he proceeded to make his proposed invention. He took out a patent for it in 1778, describing himself in the specification as "of Cross Court, Carnaby Market [Golden Square], Middles.e.x, Cabinet Maker." He afterwards removed to a shop in Denmark Street, St. Giles"s, and while there he made a further improvement in his invention by the addition of a water c.o.c.k, which he patented in 1783. The merits of the machine were generally recognised, and before long it came into extensive use, continuing to be employed, with but few alterations, until the present day. His circ.u.mstances improving with the increased use of his invention, Bramah proceeded to undertake the manufacture of the pumps, pipes, &c., required for its construction; and, remembering his friend the Yorkshire blacksmith, who had made his first tools for him out of the old files and razor-blades, he sent for him to London to take charge of his blacksmith"s department, in which he proved a most useful a.s.sistant. As usual, the patent was attacked by pirates so soon as it became productive, and Bramah was under the necessity, on more than one occasion, of defending his property in the invention, in which he was completely successful.
We next find Bramah turning his attention to the invention of a lock that should surpa.s.s all others then known. The locks then in use were of a very imperfect character, easily picked by dexterous thieves, against whom they afforded little protection. Yet locks are a very ancient invention, though, as in many other cases, the art of making them seems in a great measure to have become lost, and accordingly had to be found out anew. Thus the tumbler lock--which consists in the use of moveable impediments acted on by the proper key only, as contradistinguished from the ordinary ward locks, where the impediments are fixed--appears to have been well known to the ancient Egyptians, the representation of such a lock being found sculptured among the bas-reliefs which decorate the great temple at Karnak. This kind of lock was revived, or at least greatly improved, by a Mr. Barron in 1774, and it was shortly after this time that Bramah directed his attention to the subject. After much study and many experiments, he contrived a lock more simple, more serviceable, as well as more secure, than Barron"s, as is proved by the fact that it has stood the test of nearly eighty years" experience,[1] and still holds its ground. For a long time, indeed, Bramah"s lock was regarded as absolutely inviolable, and it remained unpicked for sixty-seven years until Hobbs the American mastered it in 1851. A notice had long been exhibited in Bramah"s shop-window in Piccadilly, offering 200L. to any one who should succeed in picking the patent lock. Many tried, and all failed, until Hobbs succeeded, after sixteen days" manipulation of it with various elaborate instruments. But the difficulty with which the lock was picked showed that, for all ordinary purposes, it might be p.r.o.nounced impregnable.
The new locks were machines of the most delicate kind, the action of which depended in a great measure upon the precision with which the springs, sliders, levers, barrels, and other parts were finished. The merits of the invention being generally admitted, there was a considerable demand for the locks, and the necessity thus arose for inventing a series of original machine-tools to enable them to be manufactured in sufficient quant.i.ties to meet the demand. It is probable, indeed, that, but for the contrivance of such tools, the lock could never have come in to general use, as the skill of hand-workmen, no matter how experienced, could not have been relied upon for turning out the article with that degree of accuracy and finish in all the parts which was indispensable for its proper action. In conducting the manufacture throughout, Bramah was greatly a.s.sisted by Henry Maudslay, his foreman, to whom he was in no small degree indebted for the contrivance of those tool-machines which enabled him to carry on the business of lock-making with advantage and profit.
Bramah"s indefatigable spirit of invention was only stimulated to fresh efforts by the success of his lock; and in the course of a few years we find him entering upon a more important and original line of action than he had yet ventured on. His patent of 1785 shows the direction of his studies. Watt had invented his steam-engine, which was coming into general use; and the creation of motive-power in various other forms became a favourite subject of inquiry with inventors. Bramah"s first invention with this object was his Hydrostatic Machine, founded on the doctrine of the equilibrium of pressure in fluids, as exhibited in the well known "hydrostatic paradox." In his patent of 1785, in which he no longer describes himself as Cabinet maker, but "Engine maker" of Piccadilly, he indicated many inventions, though none of them came into practical use,--such as a Hydrostatical Machine and Boiler, and the application of the power produced by them to the drawing of carriages, and the propelling of ships by a paddle-wheel fixed in the stern of the vessel, of which drawings are annexed to the specification; but it was not until 1795 that he patented his Hydrostatic or Hydraulic Press.
Though the principle on which the Hydraulic Press is founded had long been known, and formed the subject of much curious speculation, it remained unproductive of results until a comparatively recent period, when the idea occurred of applying it to mechanical purposes. A machine of the kind was indeed proposed by Pascal, the eminent philosopher, in 1664, but more than a century elapsed before the difficulties in the way of its construction were satisfactorily overcome. Bramah"s machine consists of a large and ma.s.sive cylinder, in which there works an accurately-fitted solid piston or plunger. A forcing-pump of very small bore communicates with the bottom of the cylinder, and by the action of the pump-handle or lever, exceeding small quant.i.ties of water are forced in succession beneath the piston in the large cylinder, thus gradually raising it up, and compressing bodies whose bulk or volume it is intended to reduce. Hence it is most commonly used as a packing-press, being superior to every other contrivance of the kind that has yet been invented; and though exercising a prodigious force, it is so easily managed that a boy can work it. The machine has been employed on many extraordinary occasions in preference to other methods of applying power. Thus Robert Stephenson used it to hoist the gigantic tubes of the Britannia Bridge into their bed,[2] and Brunel to launch the Great Eastern steamship from her cradles. It has also been used to cut bars of iron, to draw the piles driven in forming coffer dams, and to wrench up trees by the roots, all of which feats it accomplishes with comparative ease.
The princ.i.p.al difficulty experienced in constructing the hydraulic press before the time of Bramah arose from the tremendous pressure exercised by the pump, which forced the water through between the solid piston and the side of the cylinder in which it worked in such quant.i.ties as to render the press useless for practical purposes.
Bramah himself was at first completely baffled by this difficulty. It will be observed that the problem was to secure a joint sufficiently free to let the piston slide up through it, and at the same time so water-tight as to withstand the internal force of the pump. These two conditions seemed so conflicting that Bramah was almost at his wit"s end, and for a time despaired of being able to bring the machine to a state of practical efficiency. None but those who have occupied themselves in the laborious and often profitless task of helping the world to new and useful machines can have any idea of the tantalizing anxiety which arises from the apparently petty stumbling-blocks which for awhile impede the realization of a great idea in mechanical invention. Such was the case with the water-tight arrangement in the hydraulic press. In his early experiments, Bramah tried the expedient of the ordinary stuffing-box for the purpose of securing the required water tightness" That is, a coil of hemp on leather washers was placed in a recess, so as to fit tightly round the moving ram or piston, and it was further held in its place by means of a compressing collar forced hard down by strong screws. The defect of this arrangement was, that, even supposing the packing could be made sufficiently tight to resist the pa.s.sage of the water urged by the tremendous pressure from beneath, such was the grip which the compressed material took of the ram of the press, that it could not be got to return down after the water pressure had been removed.
In this dilemma, Bramah"s ever-ready workman, Henry Maudslay, came to his rescue. The happy idea occurred to him of employing the pressure of the water itself to give the requisite water-tightness to the collar. It was a flash of common-sense genius--beautiful through its very simplicity. The result was Maudslay"s self-tightening collar, the action of which a few words of description will render easily intelligible. A collar of sound leather, the convex side upwards and the concave downwards, was fitted into the recess turned out in the neck of the press-cylinder, at the place formerly used as a stuffing-box. Immediately on the high pressure water being turned on, it forced its way into the leathern concavity and "flapped out" the bent edges of the collar; and, in so doing, caused the leather to apply itself to the surface of the rising ram with a degree of closeness and tightness so as to seal up the joint the closer exactly in proportion to the pressure of the water in its tendency to escape. On the other hand, the moment the pressure was let off and the ram desired to return, the collar collapsed and the ram slid gently down, perfectly free and yet perfectly water-tight. Thus, the former tendency of the water to escape by the side of the piston was by this most simple and elegant self-adjusting contrivance made instrumental to the perfectly efficient action of the machine; and from the moment of its invention the hydraulic press took its place as one of the grandest agents for exercising power in a concentrated and tranquil form.
Bramah continued his useful labours as an inventor for many years. His study of the principles of hydraulics, in the course of his invention of the press, enabled him to introduce many valuable improvements in pumping-machinery. By varying the form of the piston and cylinder he was enabled to obtain a rotary motion,[3] which he advantageously applied to many purposes. Thus he adopted it in the well known fire-engine, the use of which has almost become universal. Another popular machine of his is the beer-pump, patented in 1797, by which the publican is enabled to raise from the casks in the cellar beneath, the various liquors sold by him over the counter. He also took out several patents for the improvement of the steam-engine, in which, however, Watt left little room for other inventors; and hence Bramah seems to have entertained a grudge against Watt, which broke out fiercely in the evidence given by him in the case of Boulton and Watt versus Hornblower and Maberly, tried in December 1796. On that occasion his temper seems to have got the better of his judgment, and he was cut short by the judge in the attempt which he then made to submit the contents of the pamphlet subsequently published by him in the form of a letter to the judge before whom the case was tried.[4] In that pamphlet he argued that Watt"s specification had no definite meaning; that it was inconsistent and absurd, and could not possibly be understood; that the proposal to work steam-engines on the principle of condensation was entirely fallacious; that Watt"s method of packing the piston was "monstrous stupidity;" that the engines of Newcomen (since entirely superseded) were infinitely superior, in all respects, to those of Watt;--conclusions which, we need scarcely say, have been refuted by the experience of nearly a century.
On the expiry of Boulton and Watt"s patent, Bramah introduced several valuable improvements in the details of the condensing engine, which had by that time become an established power,--the most important of which was his "four-way c.o.c.k," which he so arranged as to revolve continuously instead of alternately, thus insuring greater precision with considerably less wear of parts. In the same patent by which he secured this invention in 1801, he also proposed sundry improvements in the boilers, as well as modifications in various parts of the engine, with the object of effecting greater simplicity and directness of action.
In his patent of 1802, we find Bramah making another great stride in mechanical invention, in his tools "for producing straight, smooth, and parallel surfaces on wood and other materials requiring truth, in a manner much more expeditious and perfect than can be performed by the use of axes, saws, planes, and other cutting instruments used by hand in the ordinary way." The specification describes the object of the invention to be the saving of manual labour, the reduction in the cost of production, and the superior character of the work executed. The tools were fixed on frames driven by machinery, some moving in a rotary direction round an upright shaft, some with the shaft horizontal like an ordinary wood-turning lathe, while in others the tools were fixed on frames sliding in stationary grooves. A wood-planing machine[5] was constructed on the principle of this invention at Woolwich a.r.s.enal, where it still continues in efficient use. The axis of the princ.i.p.al shaft was supported on a piston in a vessel of oil, which considerably diminished the friction, and it was so contrived as to be accurately regulated by means of a small forcing-pump. Although the machinery described in the patent was first applied to working on wood, it was equally applicable to working on metals; and in his own shops at Pimlico Bramah employed a machine with revolving cutters to plane metallic surfaces for his patent locks and other articles. He also introduced a method of turning spherical surfaces, either convex or concave, by a tool moveable on an axis perpendicular to that of the lathe; and of cutting out concentric sh.e.l.ls by fixing in a similar manner a curved tool of nearly the same form as that employed by common turners for making bowls. "In fact," says Mr. Mallet, "Bramah not only antic.i.p.ated, but carried out upon a tolerably large scale in his own works--for the construction of the patent hydraulic press, the water-closet, and his locks--a surprisingly large proportion of our modern tools." [6] His remarkable predilection in favour of the use of hydraulic arrangements is displayed in his specification of the surface-planing machinery, which includes a method of running pivots entirely on a fluid, and raising and depressing them at pleasure by means of a small forcing-pump and stop-c.o.c.k,--though we are not aware that any practical use has ever been made of this part of the invention.
Bramah"s inventive genius displayed itself alike in small things as in great--in a tap wherewith to draw a gla.s.s of beer, and in a hydraulic machine capable of tearing up a tree by the roots. His powers of contrivance seemed inexhaustible, and were exercised on the most various subjects. When any difficulty occurred which mechanical ingenuity was calculated to remove, recourse was usually had to Bramah, and he was rarely found at a loss for a contrivance to overcome it.
Thus, when applied to by the Bank of England in 1806, to construct a machine for more accurately and expeditiously printing the numbers and date lines on Bank notes, he at once proceeded to invent the requisite model, which he completed in the course of a month. He subsequently brought it to great perfection the figures in numerical succession being changed by the action of the machine itself,--and it still continues in regular use. Its employment in the Bank of England alone saved the labour of a hundred clerks; but its chief value consisted in its greater accuracy, the perfect legibility of the figures printed by it, and the greatly improved check which it afforded.
We next find him occupying himself with inventions connected with the manufacture of pens and paper. His little pen-making machine for readily making quill pens long continued in use, until driven out by the invention of the steel pen; but his patent for making paper by machinery, though ingenious, like everything he did, does not seem to have been adopted, the inventions of Fourdrinier and Donkin in this direction having shortly superseded all others. Among his other minor inventions may be mentioned his improved method of constructing and sledging carriage-wheels, and his improved method of laying water-pipes. In his specification of the last-mentioned invention, he included the application of water-power to the driving of machinery of every description, and for hoisting and lowering goods in docks and warehouses,--since carried out in practice, though in a different manner, by Sir William Armstrong.[7] In this, as in many other matters, Bramah shot ahead of the mechanical necessities of his time; and hence many of his patents (of which he held at one time more than twenty) proved altogether profitless. His last patent, taken out in 1814, was for the application of Roman cement to timber for the purpose of preventing dry rot.
Besides his various mechanical pursuits, Bramah also followed to a certain extent the profession of a civil engineer, though his more urgent engagements rendered it necessary for him to refuse many advantageous offers of employment in this line. He was, however, led to carry out the new water-works at Norwich, between the years 1790 and 1793, in consequence of his having been called upon to give evidence in a dispute between the corporation of that city and the lessees, in the course of which he propounded plans which, it was alleged, could not be carried out. To prove that they could be carried out, and that his evidence was correct, he undertook the new works, and executed them with complete success; besides demonstrating in a spirited publication elicited by the controversy, the insufficiency and incongruity of the plans which had been submitted by the rival engineer.