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stacle as possible may be opposed to the ascending water: c, c,c, the piston, the handle, and the lever, on which it works, all in one piece; the piston part is curved, to correspond with the curvature of the barrel: d, the pivot on which the lever of the handle works: e, a flat plate to which the whole apparatus is fastened, and which may itself be screwed to a block of wood fixed against the wall.

Mr. Eve's patent pump is probably one of the most ingenious and valuable inventions of its kind that has appeared of late years; there are no valves to open and close, the moving parts being rotatory; their speed may therefore be increased at pleasure, and to an almost unlimited degree. The water pumped up is in proportion to the speed of the revolving parts, and to the force applied. Figs. 5, 6, will, however, best illustrate its construction. A shows a front view; and B an interior view; after the end of the case with the cog-wheels is removed.

The principle is this: two cylinders of equal diameter (three inches and a half) and equal length (six inches), move in close contact on axes or pivots, and revolve in opposite directions, in an outer case or box. These cylinders have each two wings, of three-fourths of an inch area, and two grooves; and, as they revolve, the wing of one cylinder falls regularly into the groove of the other, alternately, and so in rotation; and in order that the groove may present itself regularly to the wings of the opposite cylinder, and let them pass, cog-wheels, placed outside the case, are fixed to the axes or pivots, which project: these cog-wheels insure not only an even revolution of the two moving parts, but they communicate the power, which is applied by means of a handle, to the axis of a large toothed wheel gearing into one of the two cog-wheels.

The pump-case is placed upon a common pipe, descending down to the well twenty-one feet below. Two men, turning the handle, raise half a ton of water in three minutes with this small pump; which is allowed to be a most satisfactory result, considering that, as the first pump constructed on this principle, it has of course many imperfections.

By substituting an air-vessel, with a hose and pipe, the machine becomes the most simple, strong, and effectual fire-engine. It may be converted into a water-wheel, where a small stream with a high fall of water exists, or be acted upon by steam as a rotatory steam-engine.

The advantages which it possesses over common pumps are manifold and self-evident. The most conspicuous are, a saving of power, on account of the friction being much less than in ordinary pumps. It requires no leathering, being made entirely of metal; it does not wear, as no parts touch or rub, except the axes or pivots on their bearings. Its simplicity, strength, and elegance, and the ease with which it is turned into a fire-engine, the saving of room, and weight in pump work, if applied to deep wells or shafts in mines, the advantages as a ship's pump, are peculiar, and too numerous here to enumerate.

Mr. William Brunton, of Butterly iron works in Derbyshire, has presented to the Society of Arts an improved pump for mining, which ob

viates many difficulties connected with the ordinary arrangements. To prevent the pump drawing air, he has introduced a side pipe, connecting the parts of the working barrel which are above and below the bucket, which pipe has a stop valve, that the miners can regulate with the greatest ease, so as to keep the engine to its full stroke, without drawing air, by letting down the water from the upper part of the barrel into the lower, so that it is working again in its own water. Instead of having the whole weight of the lower lift of pumps standing on the bottom, it is fixed in the pit by cross beams, and the miner has only to fit and move an additional pipe or wind-bore, which slides upon the lower length of the pump like a telescope, to lengthen down, and this additional wind-bore is besides crooked, and turned aside like a short crank, which, by the facility with which it turns round in the leathered collar above the nose of it, can easily be removed into every fresh hole which is made in the bottom by the miners. The pumps are supported in the pit by beams placed across at proper distances, so as to suit the lengths of the pipes, or lengths of the pump, which are nine feet. Short pieces are laid across these, with half circular holes in them: which being put round the pump, first beneath the flanches, firmly sustain its weight, but may quickly be removed when it is required to lower the pumps in the pit; and, as they are not fastened by any bolt, they do not prevent the pumps being drawn upwards, if it becomes necessary to take out the pumps when the pit is full of water. The pumps by these means remain stationary, and the suction-pipe lengthens as the pit is sunk, until it is drawn out to its full extent; the whole column is then lowered to the next flanches, and another pipe is added to the top. The pumps being thus kept stationary till nine feet are sunk, the pipe at the top will of course deliver the water at the same level at all times, and, instead of being obliged to lengthen the column every yard sunk, it will only be necessary every nine feet. Plate III., fig. 7, explains the construction of Mr. Brunton's pump, being a section through the centre of the working barrel and suction-piece. A is the door which unscrews to get at the clack of the pump; B is the working barrel, with the bucket D working in it; E is the clack, also shown enlarged in figs. 8 and 9; F is the suction-pipe, and GG a moveable lengthening piece: this slides over, and includes the other when the pump is first fixed; but, as the pit is sunk, it slides down over the pipe F, to reach the bottom. The outside of the inner pipe F is turned truly cylindrical and smooth, and the inside of the outer pipe G, at the upper end, for about six inches down, is made to fit it. The junction is made perfect, by leathers being placed in the bottom of the cup a a, which holds water and wet clay over them, to keep them wet and pliable, and consequently air-tight. The lower extremity of the suction-pipe G, terminates in a nose R, pierced with a number of small holes, that it may not take up dirt. This nose is not placed in a line with the pipe, but curved to one side of it, like a crank, so as to describe a circle when turned round. By this means the miners, by turning it round upon the

pipe F, can always place the nose R in the deepest part of the pit; and, when they dig or blast a deeper part, they turn the nose about into it, the sliding tube lengthening down to reach the bottom of the hole, as shown in the figure. By this means there is never a necessity to set a shot for blasting so near the pump-foot as to put in any danger of being injured by the explosion, as is the case in the common pump, in which this danger can only be avoided by moving the pump-foot to one side of the pit, which necessarly throws the whole column of pumps out of the perpendicular.

The construction of the clack is explained by the preceding figs., the former being a section, and the latter a plan. LL is a cast-iron ring, fitting into a conical seat in the bottom of the chamber of the pump, as shown in fig. 10; it has two stems 1,4, rising from it, to support a second iron ring MM; just beneath this, a bar m extends across from one stem to another, and has two screws tapped through it; these press down a second cross-bar n, which holds the leather of the valves down upon the cross-bar of the ring L, and this makes it fast, forming the hinge on which the double valves open, without the necessity of making any holes through the leather, as is common; but the chief advantage is, that by this means the clack can be repaired, and a new leather put in, with far less loss of time than at present, an object of the greatest importance; for in many situations the water gathers so fast in the pit, that if the clack fails, and cannot be quickly repaired, the water rises above the clack door, so as to prevent any access to it, and there is no remedy in the common pump but drawing up the whole pile of pumps, which is a most tedious and expensive operation. In Mr. Brunton's pump, the clack can at any time be drawn out of it, by first drawing out the bucket, and letting down an iron prong Z, which has hooks on the outside of its two points: this, when dropped down, will fall into the ring M, and its prongs springing out will catch the under side, and hold it fast enough to draw it up. Another part of Mr. Brunton's improvement consists in the addition of a pipe H, which is cast at the same time with the barrel, and communicates with it at the top and bottom, just above the clack: at the upper end the pipe is covered by a flat sliding plate, which can be moved by a small rod 6, passing through a collar of leather; the rod has a communication by a lever, so that the valve can be opened or shut by the men in the bottom of the pit. The object of this side pipe is to let down such a proportion of the water which the pump draws, as will prevent its drawing air; though, of course, the motion of the engine will be so adapted as not to require a great proportion of the water to be thus returned through the side pipe, yet it will not be possible to work the engine so correctly as not to draw some without this contrivance, and, if it does, it draws up much dirt and pieces of stone into the pump, besides causing the engine to work very irregularly, in consequence of partially losing its load every time the air enters the pump. Another use of the side pipe is to let down water into the chamber of the clack to fill it, when the engine is first

set to work, after the pumps have been standing still, and the lower part of the barrel and chamber empty.

When a spiral pipe, consisting of many convolutions, arranged either in a single plane, or in a cylindrical or comical surface, and revolving round a horizontal axis, is connected at one end by a water-tight joint with an ascending pipe, while the other end receives, during each revolution, nearly equal quantities of air and water, the machine is called a spiral pump. It was invented about 1746, by Andrew Wirtz, a pewterer at Zurich. The end of this pipe is furnished with a spoon, containing as much water as will fill half a coil, which enters the pipe a little before the spoon has arrived at its highest situation; the other half remaining full of air, which communicates the pressure of the column of water to the preceding portion, and in this manner the effect of nearly all the water in the wheel is united, and becomes equivalent to that of the column of water, or of water mixed with air, in the ascending pipe. The air nearest the joint is compressed into a space much smaller than that which it occupied at its entrance; so that, where the height is considerable, it becomes advisable to admit a larger portion of air than would naturally fill half the coil, and this lessens the quantity of water raised, but it lessens also the force required to turn the machine. The joint ought to be conical, in order that it may be tightened when it becomes loose, and the pressure ought to be removed from it as much as possible. The loss of power, supposing the machine well constructed, arises only from the friction of the water in the pipe, and the friction of the wheel on its axis; and, where a large quantity of water is to be raised to a moderate height, both of these resistances may be rendered inconsiderable. But, when the height is very great, the length of the spiral must be much increased, so that the weight of the pipe becomes extremely cumbersome, and causes a great friction on the axis, as well as a strain on the machinery: thus, for a height of forty feet, Dr. Young found that the wheel required above 100 feet of a pipe which was three-quarters of an inch in diameter; and, more than one-half of the pipe being always full of water, we have to overcome the friction of about eighty feet of such a pipe, which will require twenty-four times as much excess of pressure to produce a given velocity, as if there were no friction. The centrifugal force of the water in the wheel would, also, materially impede its ascent if the velocity were considerable, since it would be always possible to turn it so rapidly as to throw the whole water back into the spoon. The machine which Dr. Young had erected being out of repair, he thought it more eligible to substitute for it a common forcing-pump, than to attempt to make any further improvement in it, under circumstances so unfavorable. But if the wheel, with its pipes, were entirely made of wood, it might in many cases succeed better; or the pipes may be made of tinned copper, or even of earthenware, which might be cheaper and lighter than lead.

The chain-pump consists of two square or cy

lindrical barrels, through which a chain passes, having a great number of flat pistons, or valves, fixed upon it at proper distances. The chain passes round a wheel, fixed at one end of the machine. The teeth of this are so contrived as to receive one-half of the flat pistons, which go free of the sides of the barrel by nearly a quarter of an inch, and let them fold in, and they take hold of the links as they rise. A whole row of the pistons, which go free of the sides of the barrel by nearly a quarter of an inch, are always lifting when the pump is at work, and, as this machine is generally worked with rapidity, they bring up a full bore of water in the pump. It is worked either by one or two handles, according to the labor required.

The many fatal accidents which happen to ships, from the choking of their pumps, makes it an important object in naval affairs to find some machine for freeing ships from water, not liable to so dangerous a defect. The chain-pump, being found least exceptionable in this respect, was adopted in the British navy; but the chainpump itself is not free from imperfections. If the valves are not well fitted to the cylinders, through which they move, much water will fall back; if they are well fitted the friction of many valves must be considerable, besides the friction of the chain round the sprocket-wheels, and that of the wheels themselves. To which may be added the great wear of leathers, and the disadvantage which attends the surging and breaking of the chain. The preference, therefore, which has been given to chain-pumps over those which work by the pressure of the atmosphere, must have arisen from one circumstance, that they have been found less liable to choke.

In point of friction, of coolness, and of cheapness, the sucking pump has so evidently the advantage over the chain-pump, that it will not fail to gain the preference, whenever it shall be no longer liable to be choked with gravel and with .chips.

Buchanan's pump, which, like the common pump, acts by the pressure of the atmosphere, is not liable to the defects incident to other pumps upon that principle, being essentially different from any in general use.

The principal object of its invention was to remove the imperfection of choking, and, in attaining this important end, a variety of collateral advantages have also been produced, which enhance its utility.

The points in which it differs essentially from the common pump, and by which it excels, are, that it discharges the water below the piston, and has its valves lying near each other.

The advantages of this arrangement are- -that the sand or other matter, which may be in the water, is discharged without injuring the barrel or the piston-leathers; so that, besides avoiding unnecessary wear and tear, the power of the pump is preserved, and not apt to be diminished or destroyed in moments of danger, as is often the case with the common and chain-pumpsthat the valves are not confined to any particular dimensions, but may be made capable of discharging every thing that can rise in the suctionpiece, without danger of being choked-that, if

there should happen upon any occasion to be an obstruction in the valves, they are both within the reach of a person's hand, and may be cleared at once, without the disjunction of any part of the pump-and that the pump is rendered capable of being instantaneously converted into an engine for extinguishing fire. Besides, it occupies very little space in the hold, and thus saves room for stowage.

But this pump is not confined to nautical uses alone; its adaptation extends to the raising of water in all situations, and with peculiar advantage where it happens to be mixed with sand or substances which destroy other pumps, as, for instance, in alum-works, in mines, in quarries, in the clearing of foundations; and in its double capacity it will be very convenient in gardens, bleaching-grounds, in stable, and farm yards, and in all manufactories, or other places, where there is a necessity for raising water and the risk of fire.

With all these advantages, it is a simple and durable pump, and may be made either of metal or wood, at a moderate expense.

Fig. 1, plate IV. HYDROSTATICS and HYDRAULICS, is a vertical section of the pump, as made of metal, in which A is the suction-piece, B the inner valve, C the outer valve.

The valves are of the kind called clack-valves. Their hinges are generally made of metal, as being more durable than leather.

D the working-barrel, E the piston, G the spout.

The following parts are necessary only when the pump is intended to act as a fire-engine.

H an air-vessel, which is screwed like a hosepipe, that it may, at pleasure, the more readily be fixed or unfixed.

There is a perforated stopple for the spout, made for receiving such pipes as are common to fire-engines. It is oval and tapered, and, being introduced transversely, upon being pulled back, becomes immediately tight.

These parts being provided, all that is necessary to make the pump act as a fire-engine, after having been used as a sucking-pump, is to plug up the spout with the stopple.

No particular mode being essential in the working of this pump, it may, according to choice, or circumstances, be wrought by all the methods practised with the common pump. In many cases, however, it may be advantageous to have two of them so connected as to have an alternate motion, in which case one air-vessel, and even one suction-piece, might serve both.

The usual method of working pumps, either in distilleries, &c., or on board ships, is to force the water to the top of the barrel, and allow it to run off to a lower level.

It is quite clear that, if the water in this case descends from the top of the pump to a place of delivery much below the top of the pump-barrel, the fall of the water through this height is a mechanical force which is entirely wasted, and which may be actually employed in raising the water through a part of the pump-barrel. Mr. Witty avails himself of this power in a very ingenious manner. Instead of letting the water or liquid escape from a common pump, at the

usual place of delivery, I caused it to desc.nd again in a syphon-pipe to the lowest level at which it can conveniently be delivered; and as this descent is considerable in ships, brewhouses, &c., a considerable saving of labor is effected in working pumps by a descending column of water or liquor, counterbalancing as much in length of the rising column in the pump, as the height which it descends in the syphon-pipe, to the place where it can be delivered.'

We have no doubt that this invention will be found to be of great practical value, as it relieves the men at the pump of a very great part of their labor. In cases of danger, at sea, it may prove the means of saving both the ship and the crew.

If we consider the water, which in ordinary pumps falls from the top of the barrel to the place of its reception, as a faechanical free which is lost, we may avail ourselves of it, by var.ous contrivances, for assisting in the work to be performed. In Mr. Witty's contriv mce, the men at the pamp raise the water to the bottom of the short leg of the syphon, and it is then drawn through the syphon by the action of the longer branch. There are many cases, however, when we may allow the men to raise the water to the top of the barrel, and employ the direct force of the descending fluid to work another pump, or perform any other piece of work that may be requied.

Mr. Robert Clarke, of Sun lerland, has proposed an improvement in the mode of applying men's force to pumping, which is worthy the consideration of scamen. It is to chance the posture of standing to sitting, and making the action the same as that of rowing, which, besides that it is by philosophers considered as the most efficacious application of a man's force, is to seamen most particularly so from their habitual practice of it. He objects to the ordinary action of pumping with a brake, as the posture is weak, and requires much force to preserve it. It oppresses the man by over-stretching his loins on one side, and incommodes respiration by the flexure of the body on the other side. Too much motion of the shoulder-joint is required, as the mu-cles which act on the arm-bone at this joint, are disproportionate to the effort they must make, when the arm vibrates on the shoulder-joints as a centre, for the force to be communicated by the hand. Besides this, the arms themselves are at one instant enfeebled, by being thrown above the head and requiring a pull, and the next instant requiring a pushing effort; which changes of direction, in the exertion and sustaining force, are too continual and rapid for long continuance; in standing, too, the body is a continued deal weight upon the logs.

The action of rowing is powerful to a surprising de, ree, and so well adipted to a man's ease, that he can continue it a greater length of time without fatigue, than any other raode of exertion; for, though the motion is large, it is made up of easy motions in several joints; the velocity and resistance of which, suit the muscles employed. Very little sustaining force is required; for the body is supported, an tuns unloaded to its charge: the breathing so is free. The manner

carrying this intellect is very simple: the

lever or brake bring bent at right angles at a centre pin, so that it hangs straight down when it is at rest, astead of being horizontal; then to the lower extremity a rod is jointed, which is carried rather in an inclined direction upwards to the seaman, who is seated before the pump with a rest for his feet. The rod has a cross handle, to hold by both hands, and in some cases it may be made long enough for two men to sit side by side upon the same seat; and by drawing and pushing it, in the same manner as rowing, the perpendicular lever is caused to vibrate, and the horizontal arm, or bended part which suspends the pump spear, partakes of the motion sufficiently for pumping.

The latest improvements in ship-pumps are by captain Jekyl. This gentleman has invented an addition to the pump of an air vessel, and a stuffing-box for the rod to pass through, by which it will raise the water to a greater height than the head of the pump, and a hose being attached to the pump spout, by very simple means, the water is conveyed to any desired port of the ship, and thrown in a jet through a nose-pipe with great force, to extinguish fire, if such a calamity should befal a ship, and thus the pump is rendered of two-fold service. The idea of converting the pump to a fire-engine is not new, having been attempte in many dith rent ways by forcing-pum; but these having pipes procced. ing from the lower port of the bar Is and valves, which are not very accessible, are always liable to choke up by obstructions, and have not succeeled in general use. The air-vessel has always been in the way, if made of a sufficient size to answer the purpose of equalizing the stream. Captain Jekyl has obviated these objections, and, without altering the material parts of the handpump, has rendered it as complete a fire-engine as can be wished. This is explained by fig. 2, plate IV., which is a section of the pump through its whole length. ABC is the iron brake or lever to work it. It is branched at the same extreme end, and has a wooden pole, C, fixed in it, for several men to hold at once: D is the iron stanchion or fulerum of the brake; it is fixed to the pump-head by means of strong iron hoops at EE and FF, which at the same time strengthen the work of the pump The centre-pin is to be at a height of two feet six inches above the ship's deck. II are the slings of the pump, united by a firlock or pin to the end of the brake, and suspending the pump-spear I, by means of the joint-piece g. IK is the pump-spear, made of copper in the upper part I, a d the lower length K of iron: the latter has the bucket M attached to it. The valve of the bucket is made in a very simple and effective manner; the valve being merely a round plate of brass, with a hole through the centre to receive the rod, upon which it rises and falls, and covers the aperture in the bucket. The bucket is a ring of brass, with a cross bar to fix the rod in: it is made in two thicknesses, one above the other, and a cup of leather is held in between them, projecting all round the upper part of the bucket, and turning up, to make a tight fitting in the barrel. The two rings of the bucket are held together by the piston-rod passing through both, and a cross-wedge beneath.

L is the brass chamber in which the bucket works: it is well fitted into the wood of the pumptree, so that the water cannot leak by it, and is bored smooth withinside. N is the lower box, fitted into the lower part of the pump-tree, beneath the chamber: it has a groove round it into which oakum is placed, and when it is put down makes a tight joint: its valve is of the same construction as that of the bucket, with the addition of a ring or eye on the top of the pin, on which the valve rises and falls. By this eye the box can be drawn up when it needs repair, by first drawing up the bucket of the pump, and putting an iron hook down into this eye. OOP is the air-vessel: this is a cylinder of sheet copper, soldered to a cover of brass; within the centre of it is a tube, likewise soldered to the cover, through which the copper pump-spear passes, and is fitted round at top with a collar of leather and stuffing. To prevent the escape of the water, it is packed with hemp and two rings of leather. R shows the place of two iron bars, fitted through the head of the pump, and confining the cover, OO, of the air-vessel; they are fastened by the wedges d: it is by these only that the air-vessel is held down: a circle of leather is first put round the air-vessel, just beneath its lid, and this, being pressed upon the recess in the wood, makes the joint tight. I is the pump nozzle, which delivers the water. When it is used as a fire-engine, a hose is fixed on by its link-joints, and keys or wedges: the nozzle is fixed to the pump by four screw-bolts going through the thickness of the pump, and is fixed in such a direction as will most conveniently lead to a receiver which unites the hoses from all three of the ship's pumps.

Fig. 3 is the link joint of the hose, T representing the pump-spout, made of cast iron, and screwed to the pump-tree; ee is the collar or socket, made of brass, with the hose X bound upon it. This has two trunnions, on which a link, f, is fitted, one on each side; these links pass through grooves in the cast-iron piece T, and a key g, put down through the link behind it, draws the joint tight, without any screwing or farther trouble. The socket ee is fitted into the nozzle, and has a leather ring to make it tight. The outside of the pump is to be hooped at every three feet, to prevent it from bursting by the pressure of the water. The disposition of the three hand-pumps in a ship's well renders their connexion with a common receiver very convenient to bring all the water into one stream, which will then be very powerful, and more capable of extinguishing a fire than any moveable engine. Two hand-pumps are always placed on the starboard side of the main-mast, in the well, and one of them being the cistern pump, used for washing decks, its foot stands upon a small cistern fixed upon the step of the main-mast, and supplied with water by a pipe through the ship's side, with a cock to admit it at pleasure; there is one pump on the larboard side of the mast, three separate hoses being united with each of the pumps by a link-joint at one end, and, with three necks attached by similar joints at the other, bringing all the water into one; and a hose being Joined by a link-joint, , to the opposite end of

the receiver, conveys the whole water to any part of the ship. The receiver has the three nozzles kkk at one end made in a divergent direction, agreeably to the directions in which the hoses come from the three different pumps, and a valve is placed withinside, before each hose, to open inwards, in order that the receiver may be used for one or two pumps, whilst the others are repairing or getting ready, or that, if any of the hoses burst, the water may not escape from the receiver at that nozzle. There are two handles fixed to the receiver, to lift and carry it, as it is to be moveable, and when in use is proposed to be laid on the grating of the main hatchway, as the most central situation, from which the hose may be carried in any direction. Z is a branch pipe, or jet, screwed at the end of the great hose X; and it also unscrews at the extreme end, to fit on jets of different bores, in the same manner as all other fire-engines. In working, the pressure of the water condenses the air contained in the receiver, OOP, into a small space, and its reaction to resume its former bulk equalizes the efflux of water from the nozzle of the pump.

In some experiments it performed as well as could be desired, a single pump forming a very effective engine; but, when the three were combined, it was superior in force to any ever seen, and would throw a stream of an inch in diameter over the main top-mast head of a seventy-four gun ship. Besides, the length of the handle C admitting several men to work at once, an accession of force is gained by a rope n, made fast to the brake AB, and conducted through a single block, hooked to the deck at m, and thence along the ship's deck. At this any number of men may be applied very advantageously to produce the stroke, leaving those at the handle only to return it by lifting the handle. If the ship proves leaky, and the stuffing-box is thought to be an obstruction to the working of the pump, the airvessel may be taken out, by drawing the wedges d, and taking out the bars R, which confine it; then after taking out the key which connects the joint-piece g with the copper rod, also removing the brake, lift out the air-vessel by the two screws of the stuffing-box, and fix on the joint-piece again; but fix the guide-eye H in the lowest pair of holes, so that it will receive the top of the copper rod, and prevent the pump-spear having any play in the slings. In this state it acts as a common hand-pump, but the air-vessel can be restored to its place and be ready for work in two minutes. To prevent any of the work being neglected from carelessness, the inventer proposes that one of the pumps shall be always used to wash the ship by the hose and jet in the morning, which it would do much more effectively than by the present mode of raising the water into buckets; and the force with which the jet of water is thrown would very completely wash into every recess of the gun-carriages, and other places where a brush cannot reach; while, by this constant exercise, the pumps would always be ready, at a moment's notice, on an alarm of fire.

The following simple and ingenious method of working a ship's pump, when the crew are either too few in number, or too much exhausted

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