among mechanical inventors and merchant adventurers, the rewards of industry are divided into great prizes and blanks. Success admits the aspirant within the dazzling circles of wealth and fame; failure condemns him to oblivion, and too often to penury. Whatever may be the effect upon individuals-and to him who has aimed high, even failure is not without its consolations-there can be little doubt, that in a national point of view the results are advantageous. The general standard of excellence is raised. When more men 'dare greatly,' more will achieve greatly. A larger amount of talent is allured to engage in active careers, and to endure in patience their inevitable fatigues and disappointments; while from time to time, discoveries and works of magnificent novelty and utility are contributed as additions to the stores of national wealth. 66 Projectors, since the days of Laputa, and long before, have provoked the ridicule of the wits. It was not till Adam Smith had added the gravity of his censure, that Bentham, writing from Crichoff in White Russia, and full of fellow-feeling for them, interposed in their behalf in a letter of remonstrance, the justice of which Adam Smith admitted. In proof of their national importance, (for Manchester was then but in its cradle,) Bentham relied on Adam Smith's own examples: Birmingham and Sheffield (he replies) are pitched upon by you as examples, the one of a projecting town, the other of an unprojecting one. Can you forgive my saying, I rather wonder that this comparison of your own choosing did not suggest some suspicions of the justice of the conceptions you had taken up to the disadvantage of projectors? Sheffield is an old oak, Birmingham but a mushroom. What if we should find the mushroom still vaster and more vigorous than the oak?* Not but the one as well as the other, at what time soever planted, must equally have been planted by projectors; for though Tubal Cain himself were to be brought post from Armenia to plant Sheffield, Tubal Cain himself was as arrant a projector in his day as even Sir Thomas Lombe was, or Bishop Blaize." The earnestness with which he returned to the subject in his "Manual of Political Economy," shows the value which he attached to it. "As the world advances, the snares, the traps, the pitfalls, which inexperience has found in the path of inventive industry, will be filled up by the fortunes and the minds of those who have fallen into them and been ruined. In this, as in every other career, the ages gone by have been the forlorn hope, which has received for those who followed them the blows of fortune. There is not one reason for hoping less well of future projects than of those which are past, but here is one for hoping better. Nothing would more contribute to the preliminary separation of useless from useful projects, and to secure the laborers in the hazardous routes of invention from failure, than a good treatise upon projects in general. It would form a suitable appendix to the judicious and philosophical work of the Abbé Condillac upon systems. What this is in matters of theory, the other would be in matters of practice. The execution of such a work might be promoted by the proposal of a liberal reward for the most instructive work of this kind. "A survey might be made of the different branches of human knowledge; and what each presents as most remarkable in this respect might be brought to view. Chemistry has its philosopher's stone; medicine its universal panacea; mechanics its perpetual motion; politics, and particularly that part which regards finance, its method of liquidating, without funds and without injustice, national debts. Under each head of error, the insuperable obstacles presented by the nature of things to the success of any such scheme, and the illusions which may operate upon the human mind to hide the obstacles, or to nourish the expectation of seeing them surmounted, might be pointed out. Above all, dishonest projectors, impostors of every kind, ought to be depicted; the qualities of mind and character, which they possess in common, should be described. But throughout the whole work, that tone of of malignity which seems to triumph in the disgraces of genius, and which seeks to envelope wise, useful, and successful projects in the contempt and ridicule with which useless and rash projects are justly covered, should be guarded against. Such is the character, for example, of the works of the splenetic Swift. Under the pretense of ridiculing projectors, he seeks to deliver up to the contempt of the ignorant, the sciences themselves. They were hateful in his eyes on two accounts: the one, because he was unacquainted with them; the other, because they were the work, and the glorious work, of that race which he hated ever since he had lost the hope of governing part of it." Abstract science, until within a comparatively recent period, was the almost exclusive occupation of all men claiming to rank among the "sect of the philosophers." "With the brilliant personal exception of Watt, they appear to have considered it beneath their dignity to carry out their learned theories into any practical or profitable employment. Great mechanical ingenuity they no doubt displayed; but it was devoted to the construction of instruments adapted to scientific research, some of which, it is true, have since been found of utility to the general public. A few investigations were diligently prosecuted which promised to be of national benefit, such as those relating to the longitude, chronometers, and the lunar theory; but they were entertained rather as favorite scientific puzzles, inherited from past generations, than as problems whose solution would prove a vast commercial good. Davy's safety-lamp was almost an exception, at the time it appeared; and people wondered to hear that Herschel had made anything in the vulgar way of money by his telescopes, or Wollaston by his platinum. "Their bays are sere, their former laurels fade," is the sentence pronounced by Byron upon the poets; but it was recorded also at that period against all laborers in the field of intellect, who might descend to trade." Byron can have little thought that it should appear in the posthumous edition of his works, that he lived to receive for copyright from Mr. Murray 23,5407. The tendencies of the present age are, perhaps, too much the reverse of this; and have become too exclusively practical. In science, as in politics, it may be an empty pedantry to recur too constantly to first principles, but it is worse than pedantry to attempt to do without them. Yet this attempt is made every day by persons who will not undertake, or cannot appreciate, the incessant labor by which the pioneer of discovery must consolidate his progress. When men of science hardly dare to assert their comprehension of the elementary principles of some novel theory, the inventor rushes in with his prospectus and patent, to turn it to account. As a matter of course, failure and loss are the result; and science itself will sometimes share the inevitable discredit, or the calm philosopher may be turned away from the investigation, which only he can follow duly, by the atmosphere of fallacy-or, to use a plain word, humbugthat has been thrown around it. Before the very alphabet of the electro-magnetic action was accurately understood, contrivances were busily placarded whereby its agency was to supersede the steam-engine. Whatever truth there may be in the facts of Phrenology or the theories of Mesmerism, has been fatally obscured through the eager determination of empirics to "work the idea" profitably. Those who have been disgusted with the puff, or pillaged by the charlatan, are not unlikely to pass upon the whole subject a hasty sentence of transportation beyond the pale of philosophical inquiry. The "curiosities of the Patent Rolls" would furnish materials for a copious chapter in some work devoted to an exhibition of the eccentricities of intellect. Even the titles affixed as labels to a multitude of inventions suggest very curious reflections. In a list of patents registered during a few months of 1846 and '47, given in the works mentioned at the head of this article, we find, along with a numerous family of contrivances for personal and household uses, one for an "anti-emergent rat-trap;" others for "improvements in bedsteads"-in piano-fortes, saddles, and pen-holders; for "a new fastening for shutters;" for securing corks in bottles; and for "certain inprovements in the manufacture of spoons." Articles of dress supply their quota. We have inprovements in "sewing and stitching;" "a new mode of applying springs to braces;" improvements in "hats, caps and bonnets;" an "improved apparatus to be attached to boots and shoes in order to protect the wearer from splashes of mud in walking" and a long list of inventions connected with the application of gutta percha. The military and naval professions appear rather out of fashion. Nevertheless an improvement is registered "in the manufacture of bayonets ;" and another for "warping and hauling vessels," the inventor being designated Commander R. N. For the literary profession an improved ink has been invented by "M. J. B. Reade, Clerk; " and a Birmingham merchant registers some new and inproved instruments or machines for effecting or facilitating certain arithmetical computations or processes." The medical profession is enriched by "a new apparatus for the treatment of distortions of the spine;" improvements in "artificial palates;" in the manufacture of epithems; "the cutting of lozenges;" and "a means or apparatus for administering certain matters to the lungs for medical or surgical purposes;" by which vague description it was intended to specify the instruments used in the inhalation of ether. 66 The arts follow naturally the professions; and we observe that the peculiar branch of art which owes so much to the genius of M. Soyer holds a deserved rank in the estiImation of inventors. They have furnished us with improvements in "the mode of making comfits," of "preserving fruit and vegetables, of "storing beer, ale, and porter;" with a new apparatus for hatching eggs," and a "collapsible tube for sauces," made by "placing a solid piece of tin upon a properly shaped matrix, when a rod of steel being forcibly impressed thereon a thin tube is formed. The sauces are enclosed in the tube and expelled by squeezing, so there is no waste or leakage, and no air admitted to corrupt the purity of gout." This invention, however ridiculous it may sound, has been found useful in other arts besides cooking; and has been adopted as a reservoir of colors for painters, and generally when it is required that substances should be preserved in a moist state and secured from atmospheric influence. 66 Inventions of grander aim are of course almost innumerable. Some are vaguely described as new modes of obtaining motive power;" others as rotary, locomotive or marine engines. A large number refer to our staple manufactures: as "machines for spinning and weaving," or for "preparing, slubbing, and roving cotton and other fibrous substances. We find one invention for "aerial locomotion ;" and several for "making roads and ways." For the agriculturist there are machines for "cutting, slicing, or otherwise dividing hay, straw, or turnips;" several improvements in "tilling land;" and one of very comprehensive character, for "certain carbonic compounds, formed of earth, vegetable, animal and mineral rubbish, fecal substances, and waste of manufactories, and certain acids and alkalies, which compounds are applicable as manures." A few inventions are of American origin, and sufficiently characteristic. One is for improvements in finishing raw-hide whips; one or two more for the manufacture of cigars; but the most curious of all is described as the "Patent Enunciator; being a substitute for the usual suit of bells in hotels." It consists of a highly ornamental rose-wood frame, on which two hundred numbers are conspicuously arranged, each ordinarily marked by a sector card delicately hung on a pivot connected with the machinery. When any one of the two hundred pulls is started, a hammer strikes on a delicately toned bell, and the figures of the corresponding number are unmasked, the vibration of the card continuing for some seconds to indicate the numbers last brought into view. The inventor, a Mr. Johnson of New York, was stated to have on hand more orders than he could supply. It is a theory rather in favor with inventors, that many of the most brilliant discoveries have been made by accident; and indeed the examples are sufficiently well known, of apparently fortuitous occurrences giving birth to very wonderful realities. But if we could inquire more accurately, we should probably learn that the lucky accident had but set in motion a certain train of thought in an already prepared mind; while by far the majority of cases exhibit to us the new discovery elaborated by reiterated trials and improvements from its rude original. A word dropped in casual conversation, suggested an idea to the mind of a clergyman (Cartwright) of practical and benevolent tendencies; which, under the influence of contradiction, became hot and strong enough to absorb all his energies for the production of a power-loom. On the other hand, we hear of a practical manufacturer (Radcliffe) becoming convinced that it was possible and desirable to effect a certain operation by machinery instead of manual labor; and shutting himself up with workmen and tools for many months, until he emerged from his seclusion with a warp dressing machine, to testify to the success of their prolonged exertions. Even the simplest looking contrivances require knowledge, especially mathematical knowledge, of no ordinary degree at every step. The mere calculation, for example, of the best form to be given to the teeth of wheels, which are intended to transmit motion reciprocally, requires a process of analysis beyond the competence of ninety-nine in the hundred even of educated men. In more primitive stages of the mechanical arts great nicety was not required. The cogs were rudely notched in the peripheries of the wooden wheels by the saw or chisel. But now that more perfect workmanship is necessary, the mechanist must form the surfaces of the teeth into such a curve, that they shall roll instead of rubbing on one another as they successively come in contact, and the friction and wear of material be thus reduced to a minimum. It is true that many of these calculations are already prepared and published in tabulated forms, and therefore the inventor is not called upon to calculate them for himself. But few can hope to become successful improvers, who are not at least competent to understand their nature, and able to determine the particular points of every new contrivance where such considerations become important. suits. No man is a prophet in his own country, and men of science are too often the least qualified to form an estimate of an invention in their for the approval of men accustomed to the routine own branch of knowledge. To submit a novelty and forms in present use, is oftentimes to ensure its rejection." The writer then proceeds, according to the invariable rule, to invoke the overworked shades of Harvey and Galileo as illustrations of his statement. A more popular suggestion has been made, that every patentee should be required to deposit in some public museum an accurate model or specimen of his invention; which would thus prove highly useful as an object of interest and instruction to others, as well as by rendering more easy of determination any litigated question of priority. We should anticipate this further advantage from the plan the attempt to construct his model would often leave the inventor self-convicted of the inutility of his scheme and save him much disappointment. Even the preparation of an accurate drawing often has a salutary effect. Mr. Babbage relates that in the construction of his calcu But was fear that what is called the Inventive Faculty is a quality far more cheap and abundant, than the patience that can trace, or the understanding that can comprehend the delicate theorems which ought to guide the inventor, and can alone shield him from failure. Ambition too perpetually misleads him, and beguiles him into attempting the grandest achievements of science, with insufficient means and imperfect knowledge. Artists who could command a decent livehood as sign-painters, still heroically starve amid their unsalable canvass daubed with pictures of the historic order! Johnson has immortalized the folly of a man who announced himself to the occupants of an inn parlor, as the Great Twalmley, inventor of the new Floodgate Iron. But so innocent a vanity hardly deserved to be treated with so much contempt. Mr. Twalm-lating machine, not one single portion of the ley had, at all events, obtained success and fortune, to justify his self-conceit. Ridicule would far more justly be bestowed upon those half-informed mechanicians, who aspire to change the whole aspect of our national industry or our system of warfare, by the application of abilities which, at best, might be usefully devoted to domestic purposes, or the invention of instruments ranking with the Floodgate Iron. Were it not that no exercise of tyranny would be more fiercely resented than any attempt to interfere with the true-born Englishman's privilege to throw away his time and money at his own pleasure, we could suggest the appointment of certain boards of examiners, whose approval should be first secured before any invention, purporting to be novel, could be admitted to the expensive honors of a patent. We well know, however, how distasteful the suggestion would prove, and how jealously an inventor would regard the opinion of any men competent to judge of the matter referred to them. A writer in the Patent Journal expresses upon this point only the prevailing sense of the public when he observes: "Hogarth said that he would allow all the world to be judges of his paintings, except members of his own profession; and, in general, scientific men would submit their ideas to the approval of all, with the exception of men of their own pur works, although these were of extraordinary complication, required any alteration after it was once made, owing to the admirable care which had been bestowed upon the drawings. It is not, however, solely with the view of saving a few inventors the pain of disappointment, that we would have the conditions and limits of practical attainment accurately traced out. Still less is it in the spirit of the ancient geographers, who drew the lines that marked the boundaries of their known world upon their maps, and then wrote "nil ultra" outside them. For to us, who have learned that the universe is inexhaustible, the time will never come when we shall believe, of any field of research, that there is nothing more to be discovered in it. But we conceive that to ascertain the precise nature and place of the obstacles which at present retard our advance, is the surest preliminary to any attempt at their removal. To know where the barrier lies, will instruct us also where lie the domains of richest promise, not yet rifled by discoverers. To know what it is, will guide us to the selection of those aids and appliances by which it is to be broken or overleapt. D Hooke has remarked, that whenever in his researches he found himself stopped by an apparently insurmountable difficulty, he was sure to be on the brink of a valuable discovery. In his day the world was so little explored, that its richest prizes might still be stumbled upon by mere chance. The philosopher upon his voyage of discovery, like Genseric upon his voyages of conquest, might abandon the helm and let his bark sail "whithersoever the winds might carry her" trusting that fortune would lead him within sight of some region wealthy and unknown, of which he could claim possession by the prior right of occupancy. But such happy casualties are now barely possible; the harvest has been too well gleaned for mere adventurers. Within the limits of the nearer horizon, science has left, in the words of the old feudal law, "Nulle terre sans seigneur;" but it must not be forgotten that she has at the same time afforded aid and means to furnish us forth for more distant enterprises. And we are enabled also to save ourselves the trouble of many a profitless voyage; for we have, by her help, in several instances accomplished that most difficult task, whether in law or physics, of proving a negative. We may feel sure that nothing more is to be done, at least in certain directions, with our present means and instruments; as their range has been already ascertained and their powers tasked to the uttermost. On an other side we can determine without the necessity for costly experiments, and indeed often by the application of theory alone, which of two or more possible arrangements of mechanism will prove most efficacious for the accomplishment of the desired purpose. In fact, the votary of science is now able to proceed towards discovery with sure and certain steps. He knows whither he is going; and he allows nothing to escape him unnoticed on the road. Every new phenomenon as it comes within his ken is duly compared with his previous experience, and is not admitted to assume its title until it has been examined and tested with the most minute accuracy. In the same manner, every deduction to which he arrives is scrutinized with jealous care, and not until it has undergone every trial that ingenuity can devise, is it permitted to take rank among the links destined to compose the great chain of his theory. The end of all his researches is indeed always kept in sight; but he never jumps at a conclusion, nor suffers his impatience for a result to hurry him into a neglect of those precautions which can alone secure for that result the certainty and precision on which its value depends. By no meteor of the marsh must the traveller be | guided, who would penetrate the trackless expanses of the Unknown! The subject we have here traced out is far too extensive for us to attempt, within our allotted limits, to fill up its outline at every point. We can but endeavor to indicate, by a few precepts and examples, the peculiar nature of the problems which every inventor will have to work out for himself, whenever he wishes to determine the limits between the possible and the impossible. The limitary principles (by which term we purpose to specify everything, whether quality or accident, which tends to limit our progress towards perfection) may be divided into two great categories-including, first, those derived from the natural properties of matter; and secondly, those arising from the construction or arrangement of the mechanism necessarily employed. The higher importance of the former class is at once manifest. Difficulties which arise from construction may be overcome or eluded; but the task is very different where we find that Nature herself raises the barrier in our path. Man has succeeded in rendering almost every quality of every various form of material substance available for some purpose of utility. On certain occasions only, and for certain purposes, some one or other of those qualities will be found to stand in the way of his success. Chemistry has gone far towards establishing the hypothesis that all natural bodies are susceptible of assuming three formsthe solid, fluid and gaseous-according to the degree of HEAT by which they are affected. At all events it is certain that heat exercises, in various proportions, such an influence on the constituent atoms as to destroy or diminish their mutual attraction; and even when the mass does not subside into fluidity, it loses its strength and cohesive properties, and becomes disintegrated. The uses to which this property of matter has been applied are infinite. Let us see how it may become a limitary principle. It is supposed that the possible heat of a burning atom (in which of course we shall find the theoretical limit) is very far above the highest known temperature attained in our furnaces; and it would consequently follow that we might more nearly approach that limit by varying the arrangement of the fuel and the supply of air for combustion. This has been accordingly done, until we have found our progress stopped by the impossibility of discovering any substance, whereof to build our furnaces, which will. |