The circumstances under which the mechanic is usually brought forward in life, are in a national point of view, as well as regards the individual, deeply to be deplored.—England has obtained celebrity all over the world for the skill and ingenuity of her workmen; but her reward has not ended in a mere name: she has experienced the more gratifying testimonials of seeing the wealth of the world in her ports, to pay her for her superiority in Arts and Manufactures. Indeed, if we trace England’s greatness to its source, we shall find it issuing from the labour and ingenuity of her operative classes. Her agriculture is adequate to the support of a small portion of her population only, and it is to her manufactures she must look for the maintenance of the remainder. It is from the same inexhaustible source that her armies have been sent to every shore, and her fleets to every sea; it is from the same source that her power and energies are everywhere seen rising in such gigantic forms, and executing such incredible operations; it is from this, too, that her philosophers are wise, her poets eminent, her statesmen eloquent: this is her universal spur to industry; remove it, destroy the manufactures of England, and her greatness is annihilated by the act; a universal palsy seizes on her powers, her resources, her genius, her name. Is it not then of the first importance that she should look on her mechanics, those who hold the germ of her eminence, with a favourable eye? Is it not the duty of her statesmen to view their country’s greatness in its cradle, and to anticipate the means best calculated to bring it forward to the best and most vigorous maturity? Yes, it may be replied, and this is already done; have we not schools in abundance for the children of all classes, have we not schools national, schools congregational, army schools, navy schools, public schools, private schools, was ever country so be-schooled as this is?—Alas! the education of our youth is miserably defective. I do not desire to put down the schools that now exist, but I should wish to see others of a much different kind established. The education now universally afforded is merely mechanical. The intellect is but little taxed, and, less still, amused by it. What is the amount of instruction penuriously dealt out to the children of our mechanics?—why, to know how to read, to mind their stops and emphasis in proper places, to write and make up pecuniary calculations, and this being done, their education is finished; they are then sent to learn their trades; the system of mechanical instruction goes on; the hands and feet and fingers must practise such and such motions by which such and such results are produced; and after all it is often found that a better workman may be constructed out of materials of wood and iron.
It is melancholy to reflect how large a field of literature has been thus left uncultivated. I lately wanted information respecting the iron trade; I desired to know what internal or chemical change takes place in the metal in its progress through various states: and I have not been able to discover that more than one simple and popular treatise on the subject has ever issued from the British press. The French have been more inquisitive on these important subjects, and some English chemists have noticed them in a desultory manner. But a full, familiar, and popular treatise on this great source of our country’s wealth is a desideratum reflecting the greatest disgrace on the system of education pursued throughout the country. It is impossible that the philosopher who sits down in his study to propound theories on subjects connected with arts and manufactures should be able to bring as much information to the task as is known to the practical man; and it is equally useless to hope that the latter can turn his experience to the same account as if he were acquainted with the peculiar knowledge of the theorist. At the first meeting of this society, I mentioned an anecdote of two individuals employed in the humble but useful calling of stone breakers; one struck each stone as it happened to lie before him; the other observed that stones broke easiest in certain directions; he applied this observation to his employment, and was thereby enabled to earn considerably more than his companion. Now this fact was known to the theorist long before, and under a proper system of education, should have been more especially known to him whose bread so materially depended on it.
I constantly observe in the streets and highways, as strong an instance as need be adduced to point out the necessity of a better national instruction. Waggons are drawn by teams of horses to the number of four or even five, placed one after the other. Now a knowledge of mechanical forces would shew, that the nearer the exerting force is placed to the draught, the greater the power; to speak in technical language, the power is inversely as the square root of the distance—thus, if one horse be nine feet distant and another sixteen (the two horses applying equal strength) the horse nearer the draught will draw four pounds for every three drawn by the more distant; for these numbers 4 and 3 are the square roots of the numbers expressing the distances 16 and 9 feet: or in other words, three horses at 9 feet distance will do as much as four 16 feet, or as 5 at 25 feet. Horses then in draught should always be put in pairs; there is an obvious inconvenience in increasing the breadth of the team; and besides those stationed too far on the side, may be as far from the centre of gravity of the draught, as if they were placed in front of the others. The want of scientific knowledge occasioned our ancestors incalculable trouble and expense. I will explain this by their aqueducts: should we require to convey water from the top of a hill or mountain to another of equal elevation, the object may be easily and at little cost effected by placing united pipes through the intermediate space, and allowing the water to enter at one end. It is obvious that it will find its level, it will run through the pipe where it has entered, and having filled the lower portion, will rise on the opposite side until it has attained the elevation at which it entered the pipe on the first hill; but before this simple principle was known, it was deemed necessary to find a level for the water; immensely high and broad walls were raised from mountain to mountain, while to save some labour and to afford some convenience, arches of proportionate magnitude were built, spanning the valley below, and on the top of this structure a canal was formed, over which a stream of water, dearer in many instances than Setin or Falernian wine was conveyed. The Architects in those days could not have been more uselessly and absurdly employed, if their genius were exercised in inventing diving bells, to secure the sea horse from drowning, or in constructing steam paddles to assist the whale; their employment was more preposterous than that of “painting the lily, or flinging fresh perfume o’er the violet.” Scientific knowledge can be a burden to none, and there are few indeed that it may not benefit. Even the frugal house-wife, who with her family partakes of the evening cup of tea, may practise a little useful economy by knowing a simple chemical principle. Some alkalis have a superior power of extracting the colouring matter from vegetables. In the tea plant, the essence which we extract by infusion is identified with this colouring matter; hence, if I put into the tea pot, during the process of infusion, a small quantity of the carbonate of soda, I shall draw forth a larger quantity of the essential tea-principle, and, of course, I shall have my tea stronger; or if I have a respect for my nerves, a less quantity of tea with a little carbonate of soda will answer my purpose.
In performing operations in certain manufacturing processes, all the assurance of success in the mind of the operator proceeds from the knowledge that, by the same means, such results have been produced before. How exceedingly slow then must be the progress of discovery and improvement. It is almost impossible in some trades, that some fortunate combination of circumstances should not occasionally take place, and that a discovery of importance should not thereby follow. It was thus that the telescope was invented. Some glasses happened to be placed by the hands of children, in such a disposition as to magnifying or reflecting powers, as that the peculiar telescopic qualities were observed. The hint was acted on, and after repeated trials and disappointments, some clumsy and inefficient telescopes were formed. But had the science of optics been known, the secret must have instantly followed; or had the construction of the human eye been previously considered (for the eye is a perfect and beautiful telescope) the hint for making an external and auxiliary eye would have been suggested by the study. But let it not be supposed that all important discoveries are already made, and that there is no opportunity for new Watts and Arkwrights to take their illustrious positions in society. Genius still has many harvests to reap, and men of common sense and common ingenuity have many opportunities of rising to wealth and respectability. Even a simple discovery in candle-making is at this moment realizing a fortune for the inventor. Many of you know the argand lamp; the burner, whether for oil or gas, is circular, and through it is a passage for a current of air; while this is freely open the volume of flame is large, and the colour of the light white, but when obstructed the flame is smaller and of a bluish colour. Most of the gas burners in the shops are on the argand principle, where the fact now stated may be brought to trial. The inventor of the patent candles had nothing to do but to transfer this well known principle to materials used in candle making; the wick is tubular, and the passage secured from obstruction by the melted wax or tallow. This was almost the whole improvement. Candles thus made, burn with a purer and larger flame, and the protection afforded to inventors by the patent laws, will I doubt not, be the cause of an abundant reward to the observer. Thousands of these discoveries will yet be made, and thousands will derive fortunes from the discoveries.
In the very same useful article, I knew an attempt made to produce improvement, which was unsuccessful, because the individual was poor, and his fellow tradesmen ignorant. Had he the means of continuing experiments, or could he have found any individual in the candle trade wealthy enough to assist him, and possessing sagacity enough to appreciate the intended improvement, I am confident the effort alluded to would have issued in merited success. The case was this. It may not be known to you, that generally, no flame can be produced without a quantity of a certain gas which is always in the atmosphere, called oxygen; if a portion of air be deprived of this gas, you can get nothing to burn in it; if you increase the quantity of oxygen, you thereby augment the flame of any substance burning in it; if you fill a vessel with pure oxygen, almost any thing will burn in it; even iron first touched with lighted tinder, will burn in it, with a light intense and beautiful. An individual in the candle trade conceived the idea of infusing this oxygen gas into tallow; his ingenuity enabled him to overcome some obstacles; the tallow was saturated with this supporter of flame, and candles were formed from it; but when the candle was lighted, it was discovered that the tallow all round was possessed with the quality of wick; it was beautifully inflammable, but the candle burned away very rapidly. From circumstances noticed above the inventor could not follow up his experiments to the point he had so nearly attained success. The art of dyeing is very imperfectly understood by those who profess it. A dyer possesses merely an imperfect art when he ought to command a perfect science. I know few, if any, trades so completely scientific, and so abounding with pleasing investigation. But there is not only the absence of this pleasure but absolute loss of money to the dyer in the composition of various dyes. This may be shewn in several ways; I shall now notice one. The science of chemistry has unfolded a singular fact, which is that bodies will not always unite in any proportions we might desire; we may take salt and water, and mix them in any proportions up to the period when the water becomes saturated, but it then finds a limit. Thus we can make water more or less salt.
Now common vitriol is a compound formed of sulphur and oxygen; two parts of the former being mixed with one of the latter; but if one unacquainted with this principle should attempt to make vitriol, and should put three parts of the sulphur to one of the oxygen, or two of sulphur to two of oxygen, there would either be a positive waste of a considerable portion of ingredients, or a new article would be formed essentially different from the desired acid. A want of knowing this valuable truth costs many an humble dyer a fortune. How evident is it then, that “Ignorance is a heavy tax.”
In the operation of tanning it might be shewn, and I trust will be shewn by gentlemen connected with this institution, both by lectures and experiments, that the exhausted tan, as it is called, contains much more of the tanning principle than has been extracted from it. Our British-oak bark is approaching a final exhaustion, and when we are driven to use the foreign only, the secret will I doubt not be discovered. When I look around me, and consider the several trades, arts and manufactures, in which many in this district are engaged, I cannot help expressing my astonishment that an Institution of this nature was not established before. Instances of the beneficial purposes it would serve, multiply on me so fast, that I might expend the time of many lectures on the subject of this evening. I do not wish to encourage fraud, but a fact now strikes me, in reference to the gold, silver, and jewellery trade, too curious to omit. I shall prepare my way by explaining a few principles respecting weight. I dare say you are aware that the air we breathe possesses weight. If you weigh a bottle under ordinary circumstances, containing air, and nothing else, and afterwards pump the air from it and weigh it again, you will find that its weight is reduced; it weighs less than when filled with air. Now if I weigh two bodies of different sizes, but of equal weights, in the open air, and then dip balance and all into water, I shall find that they are no longer equiponderant. Each article in weighing loses as much weight as is equivalent to its own bulk of the medium in which it is weighed. For instance, if I weigh a piece of timber shaped like a quart bottle and of the size of one, and in the other scale have copper weights, the timber will lose as much weight as the size of the bottle of air would weigh, and the copper loses as much weight as its own size of air would weigh. Now if I weigh them both in water, the timber will lose as much weight as a bottle of water would weigh, and the copper weight will lose as much as its bulk of water would weigh. It is evident then that the disproportion in the latter case must be much greater than in the former. This is the reason why boys lift stones in the water they could not raise on land. And this is the reason that we often find, that a commodity balances a certain weight at one time, which it will not balance at another.
The cases of air and water, as media for weighing, I have adduced as extreme cases, to explain the effects of the different states of the atmosphere; some times it is light and thin, at others dense and heavy. When air is light, bodies weighed lose little, but when it is heavy, they lose proportionably. It is then of importance in purchasing precious articles by weight, to know the state of the weather as indicated by the barometer, and to observe the same index when we sell again; the difference in silver would not be much, that of gold would be of more importance, but in the purchase of diamonds the difference in value may be very considerable. But you must observe, that as each body loses according to its bulk, so the greater disproportion in this respect, the better; a fraudulent jeweller should then have weights of wood, and he should buy when the atmosphere is light, and sell when it is heavy; the rule also will be of service with common weights to the dealers in feathers, &c. So much for honesty!
In connexion with the silversmith’s business, I shall now illustrate my subject by a reference to the art of gilding. Many of our shopkeepers are proud of having their names and callings over their shops, glittering in golden letters; and Dudley has many artists well qualified to gratify the taste. We also gild our frames for pictures and mirrors; but the gilding soon wears off, particularly that exposed to the air. The artist cannot prevent this, he has no control over the air, but the man of science has. I think I shall best illustrate my subject, by noticing the discovery of the truly beautiful principle it is now my object to unfold.
The atmosphere acts with various corroding effects on different metals, and it will, under certain known circumstances, often pass by one to seize upon another. Some years since the lords of the admiralty, struck with the amazing expense of coppering ships’ bottoms every year, (for one year, or rather one long voyage, effectually corroded and destroyed one sheathing) applied to Sir H. Davy, to know if any plan could be devised for remedying this serious evil. It would be useless for me now to enter into minute details; suffice it to say, that Sir H. Davy was fully aware of the principle noticed above, and he applied it; he connected here and there very small portions of metals, more liable under certain influences to be rusted, than the copper of the vessels; the metals he used were iron and zinc; the latter placed inside the ship, the former connecting it to the copper outside. The process was most simple,—the cost very trifling,—the success truly gratifying. It was then found that the corrosive qualities of both air and sea water were neutralized; and, fortified with this simple protection, vessels afterwards completed the whole extent of the India voyage, without the copper sheathing being tarnished. True, other difficulties made their appearance. Rust of copper is pernicious to water-worms and small marine animals, that do great injury to the bottoms of ships; and when the copper was kept free from rust, by means of Sir H. Davy’s galvanic contrivance, those little reptiles came in vastly increased numbers and strength, and achieved as much mischief as was prevented. But while ship’s bottoms are thus exposed, the principle on which it was attempted to secure them, may be applied to other purposes; amongst those is gilding. By drawing a very simple galvanic circle, made of small morsels of zinc and iron from the gilded letters or ornaments outside a shop window, the gilding may be made to retain its brilliancy for many years. Indeed simply driving a nail in the wood-work under every letter, will keep the metallic lustre outside distinct and beautiful for a much longer time, than if this were not done.