inches forward, and two feet six inches aft, averaging two feet ten and half inches, when it is well known a vessel of her dimensions will draw from six to eight fect.

In Capacity, being built without frame timbers, beams, knees, braces, &c. and from her even surface so well adapted for stowage, this ship gains upwards of forty tons, compared with a vessel of the same size.

For Durability.-When wood is in this manner closely united to wood, without any aperture to admit air or moisture, it must be in that state least liable to any of the usual causes of premature decay, and in this respect it has a most decided advantage over the old system.

For Safety. Should this vessel be cast ashore with such violence as to beat off her stem, stern-post, dead-wood, and bilge-keels, the crew and cargo would be safe, nor would she admit of water in consequence, having no bolts to draw.

This vessel may also properly be termed a life-ship; for if her bottom were perforated by striking on a sharp rock, her water-deck would still safely float her.

So different is the new system from the old, that what constitutes the entire strength of the old, would only weaken the new. The only use of timbers, knees, braces, &c. is to preserve two planks running parallel to each other in their relative positions, and which can be thus only very imperfectly effected. This vessel is braced as she is built, and building is bracing. On the old plan, the decks and sides cannot be kept completely together; on the new, wedging the sides apart till this deck is got in, strengthens the whole structure. On the new plan, no filth, foul air, or vermin, can lodge. On the old, these cannot be entirely prevented.

This vessel, combining such advantages, has been built much cheaper than on the old plan. She was built at the most conspicuous spot in the world, adjoining the eminent seat of naval architecture, the King's Dock Yard, Deptford, and examined in the progress of building, repeatedly, by men of science, commissioners, naval surveyors, and officers;-shipwrights, ship-owners, and masters of vessels, all of whom concur in admitting her superiority.

Several vessels for sea, and also inland navigation, are now building, which may be at any time inspected at the Patent Ship Building Yard, Upper Watergate, Deptford.

ANNESLEY and SOWERBY, London, October 23, 1819.

B

Extract from "A short Account of a new Patent for a Steam Engine," taken out by Sir William Congreve, Bart.

THE principle upon which I apply the elastic force of the steam, in my new method of constructing Steam Engines, is by collecting that force under the pressure of any given column of circumambient water, or other heavy fluid; so that its effect to produce motion in any direction will be regulated by the re-acting pressure of the column of such fluid, to the expansion of the steam in a contrary direction. And on this principle I give motion to a variety of different modifications, both of rotatory and reciprocating machines, with much greater facility and simplicity of construction, and with less friction, than in any other principle of Steam Engine hitherto invented.

The Plate shews a section of a Rotatory Engine on this principle in its simplest form, wherein ABCD is a boiler divided into two parts by an internal horizontal partition abcd. Now, in the lower part of the boiler CD the steam is supposed to be gene

rated; and in the upper part AB, (which is filled also with water) an over-shot water wheel W W, made either of wood, iron, or other suitable material, is suspended on its axis, so as to revolve freely therein, being completely immersed in the upper water.

rather in the bottom of the steam chamber, will always stand on a level with the top of the aperture h, for then the opposite columns of pressure condensing, the steam between them will be in equilibrium: and up to this level will the lower compartment of the boiler, while working, be always supplied through the pipe ef, though the steam cannot escape through it.

These different compartments are, in fact, one vessel or boiler, having not only a free communication with each other, but having the water in each nearly of the same temperature, the whole being set in the same furnace, and surrounded with flues; so that, in passing from one to the other, there is no loss of heat, or expansion in the steam, during the whole of the time that it is in action. In this way a rotatory motion will be produced, not acting by impulses, but revolving with a regular and constant force on the most simple principle, and by means of machinery within the compass of the most ordinary workman to execute; at the same time without loss of power by friction or refrigeration; and without valves, pistons, or any other of the complex apparatus involved, I may say, more or less in every other description of Steam Engine hitherto produced.

Under these circumstances, therefore, the motion is produced by the passage of the steam from the lower compartment of the boiler to the upper one; where it is thrown into the ascending buckets of the water wheel W W by the following arrangement for increased effect: ghi is a third compartment in the boiler, formed by the curved partition gh, the whole breadth of the boiler, and nearly adapted to the periphery of the water wheel. This compartment is subdivided by another partition kh, not closed at k, and forms a steam chamber, into which the steam enters from the lower part A B, through an opening in the horizontal partition a be, from b to c, and passes up the outer side of the partition hk, turns round at k, and forces its way down the other side of kh, by driving the water before it, until it issues with great force and velocity through the aperture h into the ascending buckets of the wheel, being compressed in the steam chamber according to the height of the column of water or other fluid thus From what has been said as to the forced down from k to h. Rushing, calculation of the force of such an therefore, with the force thus acquired engine, it is evident its power may be through the aperture h, it not only increased or diminished in proportion drives round the wheel by its energy to the specific gravity of the fluid in and expansion as it ascends, but pro- which the wheel is made to revolve. duces, by the actual displacement of Thus, if mercury were made use of all the water or other fluid in the instead of water, a vast increase of ascending buckets, a buoyant power power would be obtained; or, in other on that side of the wheel equal to the words, a much smaller wheel would actual weight of the quantity of water produce equal powers; a circumor other fluid thus displaced. The stance which, together with the conleast moving power, therefore, of such stant action and the extraordinary a wheel, independent of the energy and simplicity and compactness of its conexpansion of the steam, may be reckon- struction, seems to give this principle ed as equal to the power which the of engine peculiar fitness for steam same over-shot wheel would exert work- boats: more especially as the steam ing in air by the fall of a column of wheel may be made to move with the water or other fluid equal in quantity velocity required for the propelling to the displacement of the steam in wheels of the boat; so that the latter this case. The upper part of the boiler might be applied at once to the extreis always kept full by a common ball-mities of the axis of the former, workcock, and the water in the upper com- ing through stuffing boxes in the side partment of the boiler communicating of the boiler. with that in the lower through the bent pipe e f, the lower boiler will thus also be regularly fed; and when the steam is up, the water in the lower boiler, or

Here I have also to observe, that the steam may, if desired, instead of entering into the buckets of the wheel, on the common principle of the water

wheel, as hitherto explained from the circumference, be carried into those buckets, from the centre, through a hollow axis and radii, allowing it only to enter into the ascending buckets. These buckets also may be either open buckets, or close ones with valves; so also they may either work wholly immersed in water, or other fluid; or the fluid may be only partially employed, and the steam may be allowed to escape, as hitherto described, or it may be got rid of by condensation.

The construction of such an Engine evidently comes within the power of a very ordinary mechanic, with very humble means: and hence, every village might have its steam engine maker, as well as its smith, its carpen

COMMERCIAL RETROSPECT, NOVEMBER 23d, 1819.

ALTHOUGH the present season of the year is generally distinguished by a great inactivity in business, yet the transactions of the late month have been far from uninteresting: nay, we think symptoms of a radical improvement are apparent, and this will be more obvious on reference to our Price Current, wherein the value of most articles will be found to have experienced a manifest enhancement. There appears more confidence, and the public funds indicate a state of health, which bear us out in making the preceding remarks.

The Sugar market has been pretty lively, and purchasers have been forward in taking considerable parcels at several shillings advance.-The stock in the Importers' hands is ascertained not to exceed 9000 casks.

Of Coffee, the stock in this port is only 1100 tons, which is scarcely one-fourth of what remained in the preceding year; much attention has of late been attached to this article, and although the rates rule high, they are considered as susceptible of much greater advance. The sales of Cotton Wool comprise 26,896 bags, with little variation in price. American Cottons seem likely to maintain their value, and the falling off in the imports, cannot fail of being very sensibly felt. The state of Commerce in America, during the Summer, has been very deplorable, to which, no doubt, the pervading sickness has much contributed. The latest advices state, that happily no new cases had appeared; in the interim all vessels arriving here are subjected to quarantine. At the commencement of the present month, there were only two American vessels in our port, which may be noted as an unprecedented circumstance. The Emigration from this port has greatly fallen off, and the late arrivals have brought numerous returned Emigrants, who have crossed and re-crossed the Atlantic without obtaining the objects of their wishes.-American produce maintains its value, with a tendency to look upward. Several vessels are still expected from British America, which will bring considerable quantities of Pot and Pearl Ashes, which rather deters purchasers from acceding to the pre

sent rates.

The imports of Timber from the British settlements, have been most abundant, and the present low rates are very ruinous to the importers; it appears probable, that an import duty will be laid on in the course of the ensuing year.

All Baltic Articles are exceedingly low, particularly Tallow, which may now be purchased'at 56s.; it is not 12 months since this article was readily sold at 963. per cwt.

There has seldom been so much business done in Dye Woods, as during the past month: prices are somewhat firmer, and we are glad to find consumers coming into the market, on so large a scale.

The stocks of Rum, Brandy, and Geneva, are very plentiful, and the prices of the two latter articles are extremely low.

Hops have been in some demand, and are now increasing in value.

The prevailing easterly winds have prevented the accustomed supplies of Grain arriving from Ireland. The Corn market has been generally well attended, and most kinds have experienced an advance. Oats are in request, and are getting dearer.

Irish Provisions remain much the same.

Butters are in good demand, at an advance of 2s. per cwt.

Emigration to America, from 21st August to 21st November inclusive, 690 persons.-8 ditto, to British America.

PRINTED BY H. FISHER, LIVERPOOL, Printer in ORDINARY TO HIS MAJESTY.

Emperial Magazine;

OR, COMPENDIUM OF

RELIGIOUS, MORAL, & PHILOSOPHICAL KNOWLEDGE.

66 THE VALUE OF A BOOK IS TO BE ESTIMATED BY ITS USE."

CURIOUS AND INTERESTING EXPERI-
MENTS ON THE PRESSURE OF THE
OCEAN.

doubts of the correctness of the worthy Traveller's inference, that the porousness of the glass was the cause of the phænomena which he records; your present correspondent felt some desire to have the experiment repeated by different persons, and in other circumstances. For, were it admitted, that glass would become pervious to water, when subjected to a high degree of pressure; yet surely no one will imagine that it would become a sieve, and an ordinary sized wine bottle admit a quart of water to rush through its sides in an instant; for then must it run in streams, through pores, at least as large as straws, instead of those of indescribable minuteness, which it is obvious the pores of glass must be, if it has any at all, and to pass through which must require time in proportion to their diminutive capacity; and no velocity that is at all credible, would allow a quart to pass through an extent of surface, which a bottle affords, in any thing like a period that could be denominated sudden, or instantaneous; nothing short of hours, or days, or weeks, could be calculated upon for such a process, by any of the smallest degree of reflection.

SIR, IN the Rev. John Campbell's Travels in South Africa, a singular experiment is related to have been made by the author, in his voyage home to England, which he describes in the following words :- "We drove a cork very tight into an empty bottle: the cork was so large, that more than half of it could not be driven into the neck of the bottle. We then tied a cord round the cork, which we also fastened round the neck of the bottle, to prevent the cork sinking down, and put a coat of pitch over the whole. By means of lead we sunk it in the water. When it was let down to about the depth of fifty fathoms, the captain said he was sure that the bottle had instantaneously filled; on which he drew it up, when we found the cork driven down into the inside, and of course the bottle was full of water. We prepared a second bottle exactly in the same way, only with the addition of a sail-needle being passed through the upper part of the cork, which rested on the mouth of the bottle, and all completely pitched over. When about fifty fathoms down, the captain called out as before, that he felt by the sudden, but that it filled the bottle: what den increase of weight, that the bottle was filled; on which it was drawn up. We were not a little surprised to find the cork in the same position, and no part of the pitch broken, yet the bottle was full of water. None of us could conjecture how the water got in. There was no part of the pitch open that would admit the point of a needle. Supposing the pitch and cork both porous, it does not appear easy to account for a quart of water passing so instantaneously through so small a space; the porousness of the glass seems to be the only consideration by which we can account for the fact."Campbell's Travels, 362.

This singular account having excited some little notice, and created many No. 11.-VOL. I.

But, it is not only stated, that the rush of water into the bottle was sud

then had become of the air, with which it was previously filled? If the bottle was full of water, the air could not remain there in a state of compression; and that it passed through the pores as the water entered, seems to be contradicted by experiment, which has frequently compressed air in glass vessels, without its ever being known to escape, but by the destruction of the vessel. At any rate, it could not pass without a most extraordinary degree of compression; and if this were the case, how is it that it did not make its way out by forcing up the cork? For it is to be observed, that no power was employed to prevent the expulsion of the cork, all that was attempted was to prevent its being thrust downwards

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