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ced the opportunity of rendering honour to whom honour is due, and doing homage to the father of our experimental philosophy.

The Diving Bell, as it is called, though very dissimilar in appearance to the utensil of that name, has been long known to our speculative engineers; but its services, until of late, were of little or no utility, except in one or two solitary instances. The foundation-stone of the noble house of Mulgrave, we are told, was laid by means of a diving vessel. Indeed, it would appear, from the testimony of certain old prints, drawings, and other information now before us, that our divers of old were unable to remain long under water-half an hour, perhaps, was their longest stay; and though some of these prints actually represent venturous wights, apparently cased in leather, with breathing tubes of the same material, descending from the bells, and attached to their respective head-pieces, thereby enabling them, if we may credit the artist, to respire freely, and scramble about at their ease; yet are we somewhat sceptical in believing that they felt themselves so completely at home as the ingenious engraver would have us to imagine. Our own experience inclines us to believe that they were impostors -mere scramblers on paper, notwithstanding the very copious and highly entertaining accounts of their exploits, handsomely printed, elegantly embellished, &c. &c. These speculations are much at variance with the practical knowledge we happen to possess, and therefore do we counsel our readers to beware of book-makers, whether of the old or of the new school, even when their volumes are temptingly bound, and their plates executed by the most esteemed artists.

Smeaton was the first of our practical engineers that took the Diving Bell in hand, and used it with success. He built one of wood, sufficiently large to hold four divers, and supplied them with fresh air through a leather pipe or hose attached to the bell, and communicating with a forcing-pump above water. This ingenious contrivance enabled the workmen to continue their labour for hours together without intermission, and impresses us with a very favourable opinion of Mr Smeaton's inventive powers. Sorry are we to say, that his well-grounded expec

tations were not more fully realized. In the course of a few months the planking yielded; the fastenings gave way; the vessel became leaky, and so very insecure withal, that it was ultimately laid aside.

Rennie succeeded Smeaton as engineer to the commissioners of Ramsgate Harbour, where the wooden bell was used, and perfected what his able predecessor had so very successfully begun. Availing himself of the scientific spirit then bestirring itself in our foundries, that eminent engineer, with a sagacity peculiarly his own, constructed a diving vessel, entirely of cast-iron, with glasses in the roof to admit of light from above. Two ingeniously contrived forcing-pumps were applied, together with a portable crane and suitable appurtenances for lifting and lowering the bell. The air-pipe was also taken through hand, and every constituent part of the diving tackle so well proportioned and skilfully put together, that we question much whether or not any farther improvement can be made. This bell was used in building Ramsgate Pier.

Having thus far introduced the subject to our readers' notice, we proceed to lay down the principles upon which every Diving Bell now in use is constructed; and as they are differently shaped, and of various dimensions, we shall pick out the one most suitable in our estimation for general purposes. A vessel of this description ought to be six feet long, five feet two inches high, and four feet two inches wide, outside measure; consequently, when immersed, it will displace about 129 cubic feet of water-C. 72, or nearly so. In navigable rivers we have the ebbing and flowing tide to guard against, and in the open sea we frequently meet with strong under currents, even when the surface is perfectly smooth; of course, more weight must be added, not only to sink the bell, but also to render it steadier in the descent, and less liable to accident from any of the aforesaid causes. We may therefore safely add C. 8 to the weight of water displaced by our vessel, and scheme it so as to weigh four tons in air. Our readers, we trust, will be good enough to dispense with our finding out, by mathematical definition, or otherways, the precise thickness of metal requisite to make good our tonnage; because it would require more time so to do than

we can very well spare, and in lieu thereof, oblige us by accepting a piece of minor information; viz. a piece of cast-iron, 3.84 inches long, and an inch square, weighs one; a piece of malleable iron, 3.57 inches long, and an inch square, weighs one; and a cubic foot of water, 624 lbs. avoirdupois.

The shape, size, and weight of our bell being now determined upon, we hasten to prepare it for immersion; and as the glasses require some little consideration, we had better begin with them. They are ten in number, each 64 inches diameter, 2 inches thick on the crown, and cast in the form of lenses, being convex on the top, and flat on the lower sides, partly to strengthen, and partly to render them more serviceable. Rays of light fall ing perpendicularly on the convex sur face of a lense, converge and bisect each other at the focal point or centre from whence the convex surface is de scribed, thereby disseminating them selves more generally throughout the vessel than if both surfaces were flat. These lenses are cast in iron moulds, and lose a little of their rotundity in cooling; hence the focal points become obtuse, and consequently harmless, though we could mention one or two instances where they happened to retain their curvatures so very perfectly, as to convince the unbeliever that concentrated rays, even when they have passed through a fathom or two of water, are not to be trifled with. In the roof or crown of the bell are ten round holes, each encircled with a rebate, where the lenses are bedded in cement, and properly secured with iron flanches and copper bolts. A safety-valve is also fixed in the crown, directly under the air-pipe, and opening inward, so as to prevent the air from escaping, should any accident happen either to the hose or forcing-pump. There are two wooden seats in the bell; one at each end, and a foot-board in the middle. They slide in projecting grooves cast along with it, and are usually unshipped when the divers are at work. We may also notice a couple of ringbolts in the roof, (inside,) to which heavy bodies are suspended with slingchains, and brought above water; also two in each end, (outside,) whereunto leading or guide-ropes may be made fast; together with a strong slingchain, attached to a ridge or bracket, cast on the crown of the bell by means

of shackle-bolts. This sling-chain is hooked to that of a powerful cranepurchase, when the diving vessel is used.

The forcing-pumps discharge into a small air-chest, furnished with two internal flap valves, that open and shut alternately, as the pistons are forced upwards and downwards, in their re spective working barrels. These pis tons are coupled with guide links, and parallel rods, to a double acting crosshandled beam, or lever, so contrived, that six or even eight men may occasionally be employed. The working barrels are twelve inches long, and eight inches diameter; the pistons one inch thick each; so that the divers are supplied with about four gallons of atmospheric air at every stroke of the lever, (from 25 to 30 per minute,) a much larger supply, we allow, than is necessary for respiration, but it keeps the men cool, and costs nothing. The air-pipe, or hose, is made of strong tough leather, prepared in animal oil, and coated with canvass, well soaked in bees' wax and linseed oil, boiled to a proper consistency. Another thickness of prepared leather is then closely sewed over all, which renders the hose perfectly air-tight, and sufficiently strong for practical depth. These pipes are usually made in fifteen-feet lengths, connected to each other with screw joints, similar to those of a fire-extinguishing engine. One end is screwed to a nozel, that projects from the airvessel, or chest, and the other to a screw pipe in the bell-roof, by which means the divers are supplied with a continual current of fresh air.

Our readers being now as wise as ourselves, in so far as theory is con cerned, we will put our diving tackle in order, and proceed to some convenient river, bay, or channel, where sunken rocks impede navigation, and do our best to remove the obstruction. For this purpose we must provide ourselves with a barge of sufficient tonnage, to carry our apparatus, and accommodate our di vers; also a strong diving crane, planted equidistant from the sides and stern, capable of lifting five tons at least. The post, or upright, should turn in a centre block, firmly fixed in the bottom of the barge; the neck thereof, in a curb or collar-plate, equally well se cured to the deck, and the jib, or projecting beam, extend just as far over the vessel as safety will freely admit

of, in order that the men may have a wide range.

It is almost superfluous to say, that our crane and diving apparatus must be inade of sound, proper materials, and put together in the best possible manner; because, when men's lives are at stake, pains and expense with us are minor considerations.-But to proceed to our task. All being in readiness, and to our liking, the crane chain is hooked to the slings, the bell lifted from its place, the divers take their seats, and are lowered into the sea. Our readers will please to observe, that the vessel in which we are about to descend, is neither more nor less than an oblong iron box, of the aforesaid weight and dimensions, turned topsy-turvy, and immersed openmouth, if we may so express ourselves, consequently the novice, unaccustomed to breathe compressed air, will be apt to startle when his cage comes in contact with the water, and well he may. We can compare the momenta ry shock to nothing more aptly than the sensation we feel, on suddenly clapping our palms to our ears; only that of the bell is more violent. Should he go down to the deep from motives of curiosity, he will there learn, that the finny inhabitants are no less curious in their way than himself, particularly the junior flounders. These little creatures flutter about the lenses, and nibble with an avidity that seems to indicate how fain they would be in to see the show; and should his motive be of a higher order, he will feel gratified in witnessing the triumph of science over ignorance, folly, and be nighted superstition-science, that would have been the means, a few centuries ago, of binding the unhappy possessor to a stake in Smithfield.

As our divers descend, the water is expelled from their place of abode by the air forced into it. They feel little or no inconvenience, in moderate depths, from breathing a denser at mosphere. They go down with confidence to their daily labour, and the lenses, in clear weather, afford them abundance of light: candles are used when the sky is cloudy, or the water impure. We have not heard of a single working man, whose health hath been impaired by earning his bread at the bottom of the sea. On reaching their destination, the signal is given

by striking the bell-roof with a hammer, the sound of which tinkles up the crane chain, and apprizes their comrades of what is passing below. We pause to remark, that none but sober, patient, attentive men, should be em ployed at this kind of work, and all idle, talkative visitants, kept back, in order that the signals may be distinctly heard, and promptly attended to. We may also observe, that every signal is given with the hammer, a certain number of strokes agreed upon between the parties denoting, hoist, lower, right, left, and so on.

Should the rock, on due examination, happen to be loose or fissury, of the free or pudding-stone breed, wedges and mauls may be used with effect, and the fragments either thrown into deep water or taken up in the bell slings, as may be deemed most advisable but if otherwise, more powerful means must be resorted to. A hole of about two inches diameter, and from one and a half, to six feet deep, is jumpered in the rock and well sponged out, into which a sheet-iron cannister, containing gun-powder, is introduced. This cannister has a small iron tube of about 5-8ths of an inch diameter, securely brayed to its crown, and pro jecting a few inches above the rock. We need scarcely say that both tube and cannister must be perfectly watertight. A wadding of pounded brick is then rammed home to the charge, and carefully coated over with tough, well-tempered clay. We may as well observe, en passant, that clean sharp sand thrown loosely in and clayed over, will answer equally as well as wadding when the hole is deep and the rock not over hard. Our readers, we suspect, will greatly marvel how business can be done in such a very business-like manner, six or eight fathoms under water; but their marvel will cease when we assure them, and of our own knowledge too, that the place whereon a diving bell rests, however deep it may be, is perfectly dry for willing, experienced men to work upon, because of the air powerfully forced down from above, which can not possibly escape until it has expelled every drop of water from the diving vessel. Having done so, it naturally ascends, and causes the sea to boil, as it were, for many fathoms around where the divers are at work.

Conceiving that our readers perfectly well understand us, we will screw another tube to that on the crown of our cannister and strike the hoisting signal. As the bell ascends, another is screwed on, another and another, until we breathe the free air. Then one of our people holds the tube fast, another on deck snatches a small piece of red-hot iron from the portable furnace at hand, drops it down, and presently the rising smoke and agitated water tell us that our labour hath not been in vain.

When the agitation subsides, we lower our bell, dispose of the shattered fragments as aforesaid, and continue our labours until every impediment is removed. In this manner was Howth harbour cleared of its dangerous sunken rocks, and that of Dunleary is about to undergo the like improvement. We dismiss the subject with a random observation or two.

It is believed by many, that divers are capable of working in these vessels at any depth, but this is altogether erroneous. Ten, or at the most, twelve fathoms is the very lowest we dare venture to go. A column of water about thirty-one feet high balances a column of atmosphere of the like diameter, and as the atmosphere presses with a density equal to about 15 lbs. avoirdupois upon every square inch of

surface, we leave our readers to judge, how the man would feel three fathoms and a half lower than we have stated under a pressure of 62 lbs. upon every superficial inch of his body. True it is, he would breathe air of the like density, but we know from experience, that when the air is greatly compressed, our people become languid, spiritless, and incapable of exertion. Added to this, the latent heat contained in every particle of air forced down to the bell is compressed along with it, and becomes altogether insufferable a few fathoms under what we call diving depth.

The curious reader may satisfy himself as to this particular by experiment. Take a small tube either of glass or metal, say 3-8ths of an inch diameter, and four inches long, securely stopt at one end. Fix a bit of dried fungus to the end of a rammer, turned and leathered so as to fill the orifice correctly; then thrust your rammer smartly down the tube, and the compressed heat therein contained will ignite the fungus. Seeing the effects of condensed air in a tube of such very small dimensions, we need add no more to satisfy our friends that diving lower than twelve fathoms is neither pleasant nor profitable.

ACALUS.

THE ILLIBERAL.

No. I.

I Do not care who hears me say it, or who calls me a bigot, a brute, an illiberal, a foe to freedom, a friend to oppression, if I say that England, of all countries in the world, has had most reason to hate and to deplore, what since the accession of George III. have been called liberal ideas. I shall not reason whether these ideas are right or wrong: I shall grant them, for argument's sake, to be right; but admitting that, I must appeal to facts to prove that these right things have been of deadly injury to the interests of England.

I am a brute, you may say, if you please. I cannot help that-but I can see through a millstone, and pass by a brick wall without making a bite at

it, as sagaciously as any of my neighbours. If you like, I shall admit that I cannot reason, and can no more draw an inference than a dray-horse. I say that I can see a thing doing, and prophesy what has happened, after it is done; and making this claim, and no farther, I proceed.

If holding extensive colonieskeeping in peace a population inclined to be hostile against you-hearing all your neighbouring countries loud in the praises of your institutions, possessing dominions in which you may enrich your population-ruling undisturbed over the sea-enjoying a monopoly of manufactures-if these and other such things be of any honour, advantage, or glory to a kingdom,

these we had, and these we, by the prevalence of liberal ideas, have partly lost irremediably, and partly only retain, by our clinging to illiberality. This is no dream of mine. Before the days of George III., I mean from the Revolution downward, for I shall not go beyond that era, the statesmen who managed our interests thought, as I hope, and trust, and believe, with a very few exceptions, all English miuisters have thought, how most to uphold the honour and the interests of England. That they were Whigs, matters little. The usual malevolence and disaffection of the party gave way under the warmth of office, and there are few periods more gratifying to true Englishmen to look over, than the administration of Sir Robert Walpole. Indecent jobbing, and more indecent bribery, no doubt, prevailed to a wonderful extent, but these are the ingrained stains of Whiggism, which no change of time can wash out. It was as visible in their last glimpse of power in 1806, as in their continued sunshine of the days of the two first Georges. Charles Fox, of our own memory, was as corrupt at core as his peculating father, the founder of the Holland estates, before him. But I quarrel not much with this.

If the country is contented at home, and honoured abroad, what need we particularly care about the half-pennyworths of public plunder shared among the great men at the top of affairs? It is, besides, a thing curable at all times.

But the Opposition to these were English to the heart. They loved England, though they loved not the reigning dynasty. Some of them wished for "him who was away;" and why? Because he was of British blood. Because

"A thousand years the regal throne Had been his fathers' and his own." Because he did not say dis, and dat, and d'oder, and had no German airs of pettifogging impertinence. Others, who put up with these trifles, because they honoured the church, grieved to see that church little respected by the official descendants of republican round-heads. All the Opposition hated Hanover, and they were right, for, in those days, the interests of that most beggarly of electorates were preferred

those of England. This was, indeed, a British Opposition.

Times altered. The fears of the Pretender vanished gradually from the day of Culloden, and the young King was educated in a creed which taught him the value of, and the respect due to, the great institutions of the country. George I. was a mere man of business, full of the littleness of shabby German courts. George II. was an ass, with hardly a decent quality about him. George III. was a cultivated Englishman, whose very peculiarities and absurdities were English. The Tory party revived in his reign, and took their proper place. Those who were personally implicated in the cause of the Stuarts were fading awaytheir descendants, some, no doubt, through policy, others, beyond question, from honester motives, had firmly adhered to the House of Hanover; add to which, a large majority of the Tory party had always been as much anti-jacobite as their Whig antagonists. It was now the Whig turn to become Oppositionists, and let us see how they did it. Any one ignorant of history, who sees them now only contemptible asses, will hardly believe that when they first began the trade, they shook the empire to its very base.

The man who gave the tone and temper to modern Whiggery, was Jack Wilkes. In everything he was fitted as a Coryphæus of such a party. Profligate in private life-seditious in public-impudent in assertion-intrepid in calumny-he went nearer the character of Clodius, as painted by Cicero, than any man who ever figured in the annals of England. He was the first man who founded that mob power which has occasionally made the rabble of London almost a match for the Government and Legislature. Into his cause the Whigs entered heart and hand. They supported him through the odium of publishing obscene poetry-they backed him when he, an outlaw, contrary to all precedent and common sense, started as a candidate for Parliament. They gave currency to his writings, conspicuous not more for ribaldry than sedition. There was little talent, it is quite true, in the ministry which they opposed; but, in order to obtain a triumph over that ministry, they jeopardied, not to say all the principles of the constitution, but the very existence of the monarchy.

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