Some of the most valuable inventions have descended to us without the names of their authors having been preserved. We are the inheritors of an immense legacy of the results of labour and ingenuity, but we know not the names of our benefactors. Who invented the watch as a measurer of time? Who invented the fast and loose pulley? Who invented the eccentric? Who, asks a mechanical inquirer,[13] "invented the method of cutting screws with stocks and dies? Whoever he might be, he was certainly a great benefactor of his species. Yet (adds the writer) his name is not known, though the invention has been so recent." This is not, however, the case with most modern inventions, the greater number of which are more or less disputed. Who was entitled to the merit of inventing printing has never yet been determined. Weber and Senefelder both laid claim to the invention of lithography, though it was merely an old German art revived. Even the invention of the penny-postage system by Sir Rowland Hill is disputed; Dr. Gray of the British Museum claiming to be its inventor, and a French writer alleging it to be an old French invention.[14] The invention of the steamboat has been claimed on behalf of Blasco de Garay, a Spaniard, Papin, a Frenchman, Jonathan Hulls, an Englishman, and Patrick Miller of Dalswinton, a Scotchman. The invention of the spinning machine has been variously attributed to Paul, Wyatt, Hargreaves, Higley, and Arkwright. The invention of the balance-spring was claimed by Huyghens, a Dutchman, Hautefeuille, a Frenchman, and Hooke, an Englishman. There is scarcely a point of detail in the locomotive but is the subject of dispute. Thus the invention of the blast-pipe is claimed for Trevithick, George Stephenson, Goldsworthy Gurney, and Timothy Hackworth; that of the tubular boiler by Seguin, Stevens, Booth, and W. H. James; that of the link-motion by John Gray, Hugh Williams, and Robert Stephenson.
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 Godfrey 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 circumstance 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 principal 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 assistance 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 circumstances 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, constituted the principal 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 classes 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 circumstances. 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 screwing 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 exactitude 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 quantity 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 principal 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.