Part 2

For the water, be the mine ever so deep, each engine working it sixty, seventy, or eighty feet high, by applying or setting the engines one over another, as shall be showed at large hereafter in the following pages, you may, by a sufficient number of engines, keep the bottom of any mine dry; and when once you know how large your feeder or spring is, it is very easy to know what sized engine, or what number of engines will do your business.

The coals used in this engine is of as little value as the coals commonly burned on the mouths of the coal-pits are; for an engine of a three-inch bore, or thereabout, working the water up sixty feet high, requires a fire-place of not above twenty inches deep, and about fourteen or fifteen inches wide, which will occasion so small a consumption, that in a coal-pit it is of no account, as we have experienced. And in all parts of England, where there are mines, coals are so cheap, that the charge of them is not to be mentioned, when we consider the vast quantity of water raised by the inconsiderable value of the coals used and burnt in so small a furnace. What the quantity of coals used for one engine in a year is cannot easily be ascertained, because of the different nature of the several sorts of coals.

As for the cure of damps by this engine, the air perpetually crowding into the ash-hole and fire-place, as it is natural for it to do, and with a most impetuous force discharged with the smoke at the top of the chimney, the contiguous air is successively following it; so that not only all steams or vapours whatsoever, that may or can arise, must naturally force its way through the fire, and so be discharged at the top with the smoke, but this motion of the fire will occasion the fresh air to descend from above down all the pits, and every where else in the mine, but down the chimney; provided you have a heading drift, or passage from all the shafts or pits in the work, to that place where the engine stands; whether the mouth of the said pit and chimney be lower or higher than the mouths of any of the rest of the pits or shafts in the same work it matters not, for here will be a perpetual circulation of the air, and with that swiftness as is hardly to be believed. This I have tried and know to be true, so leave the ingenious miner to his own judgment, whether, when all the air is in a swift motion, that any stagnation of air (which has always been adjudged the cause of damps) can happen in any pit.

CHAPTER THIRD. THE MANNER OF FIXING THE ENGINE FOR WATER-MILLS, PALACES, AND GENTLEMEN’S SEATS, AND DRAINING FENS, AND SUPPLYING HOUSES WITH WATER IN GENERAL.

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THE MANNER OF FIXING THE ENGINE FOR WATER-MILLS, PALACES, AND GENTLEMEN’S SEATS, AND DRAINING FENS, AND SUPPLYING HOUSES WITH WATER IN GENERAL.

1. For mills. The engine must be made and proportioned according to the quantity of water required to drive the mill you would make use of. Now suppose you would make a mill on a plain place, where you will have only a pond, and a small spring of water no bigger than a quill; then you must build your mill-house thirty-six feet high, in which you may make what motions, and what sort of mills you please. By the side of which house without, may be placed your water-wheel of thirty-two, thirty-three, or thirty-four feet diameter. For the height of either house or wheel I would confine no person too exactly, but I guess that a convenient height, and no more than what is common enough. Under the wheel I would have a pond, and on the top of the house a cistern of wood lined with lead. The engine may be fixed in any corner of the mill-house, twenty, twenty-one, twenty-two feet, or more, from the level of the pond: there two boilers must be fixed, as shown you in the draught for fixing the engine; and round each of them it is convenient to have a hoop of iron, with straps coming from them to rest on the brick-work, to support and strengthen them. Your clacks and pipes in the front being supported by wood, and the vessels standing on pedestals of wood, it is convenient that the flue, or chimney, be so contrived as to draw very sharp, and the flue to circulate round both the boilers, so that you may lose no part of your strength.

2. For palaces, or the nobility’s or gentlemen’s houses, you may fix the engine in any remote or out-room, whose floor is not above twenty feet from the level of your water, and you may continue your force-pipe to the top of your house, with a convenient cistern to hold your water; into which lay the pipes which may convey the water as you want it, either for pleasure or common occasions. This way of cisterns on the top of your houses or palaces would be of singular use in case of fire, as is said before; for in every staircase a pipe may go down the corner, or behind the wainscot, so as to be no blemish even to the finest of staircases. At every floor there may be a turn-cock with a screw. At the utmost end have likewise a small leather pipe, kept well oiled in a cupboard, or cavity in your wall, which may not be seen, but on the opening some part of the wainscot, or such other contrivance as the ingenious builder shall think fit to make use of. This pipe of leather must be long enough to reach from the landing-place, or stair-head, in all rooms depending thereon. One end of this pipe has a screw to fit the cock in the other pipe, and at the other end a pipe like the nose of a pair of bellows; so that wherever, though under a bed, or the remotest part of any room in the house, the fire breaks out, or is discovered, any servant having screwed the pipe to the cock, stops the nozle with his thumb till he comes to the place where the fire is, when, taking away his thumb, he, by directing the nozle to the fire, immediately extinguishes it, which being liable to be instantly used, I think a house, palace, &c. that has this invention, may be said to be morally out of danger of being destroyed, or so far injured as Whitehall and Kensington have been within a few years. This command of water must be allowed to be of vast advantage to any house whatsoever. Where brewing, washing, &c. is used, the copper standing high may be filled as easy as if it stood low, by which means the hot liquor may be contrived to go to all your coolers, and other vessels, either by a syphon, stop-cock, &c. without the hand-labour of pumping or bailing with buckets. But more conveniencies than we can at present foresee will be discovered in the use of this engine for palaces, houses, &c.

3. For fens, and the like, it is convenient that these engines be made very large; for at all small heights a small quantity of fire will deliver prodigious quantities of water. For suppose we force but thirty feet, and suck twenty feet, if the boiler does but fill the vessels, called receivers, with steam strong enough to counterpoise or exceed the force of the atmosphere, or spring of the common air, it will discharge them at so small a height as thirty feet force in a very little time; and the steam having very little force or spring is immediately condensed, so that it will presently suck full in one of the vessels while the other is discharged. Now, inasmuch as the fire being more or less adds nothing to the suction. I think such lifts, being seldom above thirty-six feet, or under six feet, all the directions further needful for fixing the engine for this use is, in all lifts under twenty-four feet, to place your engine so as a little above your force-clacks may be the place of the delivery of your water into a convenient trough or lander, to be carried off at the most proper place for its discharge. If it be any height above twenty-four feet, you have nothing to do but to continue the length of your force-pipe to the height required. It ought to have a shed or covering round it, and to be placed at the lowest place of your fen or bog, as other engines designed for that purpose commonly are.

As for fixing the engine in ships, when they may be thought probably useful, I question not but we may find conveniency enough for fixing them.

In mines and coal-pits the manner of fixing the engines is this; your pit being sunk, and a sump, or proper well, or bottom cistern, made to receive the water coming from the several feeders or springs. Supposing an engine, carrying three and a quarter inch bore, is to be fixed to deliver water about seventy feet high, constant running a full bore; in such case you make a small room in your shaft or pit, which, together with your shaft or pit, is nine feet square every way. As for example, suppose your shaft six feet by four, take three feet out of one side, and five out of another perpendicular nine feet, making a small floor or platform of boards over that part of the shaft which goes down to your sump or bottom cistern, so you have a complete room big enough for your engine, where ten or twelve people may stand on occasion. This floor may be about eighteen, nineteen, or twenty feet from the water, at the lowest you ever will draw the water into the sump or bottom cistern. If your ground be loose, it is convenient to line this room with brick; if rock, it may support itself. But in this the miner’s judgment must direct him. That the engine will stand best in the side of the pit where most is dug away, you may see in the second figure of the engine, being fixed in a mine. Your pipes, &c. must be fixed with cramps of iron, wood, or such materials as are convenient, to the side of the pit or shaft, so as to make it stand as firm as the very shaft itself. Your furnace must be so contrived, that your flame take a turn or two round each of the boilers, which any brick-layer used to furnaces can do; it being performed by running a row of bricks round them both like a screw or worm, which being contiguous to the wall of the furnaces and the boilers, makes it, as it were, a worm-funnel round them both; from whence you may continue your chimney to the top of your work, which you fasten to the sides of your shafts in the corners as you please, either with iron or wood, or both, according to the nature of the ground. And wherever you make a sudden bend or nook near a right angle in the chimney, have a loose brick or stone to take out the soot, if any should settle in such place, which in long working it may do.

SEVERAL OBJECTIONS AGAINST THE WORKING THIS ENGINE ANSWERED, IN A DIALOGUE BETWEEN A MINER AND THE AUTHOR.

A DIALOGUE BETWEEN A MINER AND THE AUTHOR.

_Miner_. Sir, having been some time concerned in the engines now used for drawing water out of our mines, and hearing so much talk of this wonderful invention of yours, of raising water by fire, I was very desirous to enter into some discourse with you concerning the nature, use, and application of your engine, so strangely differing from all other engines ever yet invented for our works, and which, you positively affirm, will every way tend so much to our advantage in the use of them; and I do not doubt of meeting with that plainness, freedom, and good humour, that your discourse is generally accompanied with. And with the same freedom resolve me in such questions as the general sense of us miners may naturally propose to object against the use of your engine, especially such of us as are yet ignorant of its use and operation, who are more capable to judge of fact, than of the nature and power of that force which raises your water.

_Author_. Sir, I am extremely obliged to you for your freedom, and shall readily embrace all opportunities to inform and explain to you the true use and nature of my engine; and, therefore, desire you, with all imaginable freedom, to proceed and ask what questions you please, either as to your own thoughts, as well as what has been suggested to you by others. And you may be assured of a plain and candid answer to all your objections.

_Miner_. Then, sir, which way will you go to work with your engine to clear an old work full of water?

_Author_. Why, sir, to deal plainly with you, if your shafts are, or may be cut straight, your tub-engines, or chain pumps, may draw forth the water. And the charge, in that respect, is not to be accounted for, because no mine would be thrown up or neglected but on account of the feeders or springs, which being certain, and constantly to be carried off winter and summer, the prospect of being likely to succeed, makes your mine worth working or emptying within twenty feet of the bottom, if ever they were worth sinking, though you work or drain by the common way of tubs or chain-pumps. And could the constant charge of those engines be afforded, numbers of them will empty and keep under any work; but it is the constant charge of carrying off what the springs bring in is the chief thing to be considered in the business of mines, which constant charge is what we lessen very much by this engine of mine.

_Miner_. What signifies your engine then, sir, if it be not capable of sinking or forking an old mine?

_Author_. Hold, my good friend, a little patience; I have dealt plainly and impartially with you about the use of your old engines: and for my engine, it will clear an old work, if full of water, as readily as your tub-gins or chain-pumps, provided the shafts are good. The method I propose to clear an old mine, if sixty feet deep, and full of water, the feeders not above two-inch bore, which is done at a very small charge after this manner; _viz_. I fix my engine on the top of the mine, and only suck and deliver a three and a quarter inch bore; as soon as we have sunk the water as far as our suction will go, which will be some twenty-two, twenty-four, or twenty-six feet deep below the surface, there I make a room fit to receive another engine, which I fix with his force-pipe to go up to the top of the pit; and when I have sunk about twenty-four or twenty-six feet more, then I fix a smaller engine of two inches bore, which, sucking twenty, and forcing forty, does your work and keeps all safe; or let your small engine be kept at work, while you remove the larger engine from the top to the middle station, and then you will have occasion for no more than two engines, the greatest of which may be removed as soon as the smaller is fixed in the lowest or proper station. And that you may be convinced of my impartiality, it is my opinion, that in gaining an old work, or sinking a new one, you use your old engines of tub or chain-pumps: this engine of mine being most proper, when you are come fairly to the bottom either of the ore or coal; for then, if you have but one lift, one station or engine-room will be sufficient. And by having two sumps or bottom cisterns, your water may, in some measure, settle in one of them in its passage to the other. So that the miners working tolerably clean, and suffering as little dead or loose coal or ore as is possible to mix with the water, you may have the water to draw only a little discoloured; for you know, as well as I, that generally the water coming from mines or coal-pits, while they work by the gins now in use, is almost clear water.

_Miner_. Sir, I thank you for your candour in relation to the clearing of an old work. But supposing that our water arises thick and muddy, which you know will sometimes happen, what shall we do with your engine then?

_Author_. What you say, sir, I know to be very true, that sometimes you have thick, muddy gravel and nasty water. To prevent which from coming into, or offending our pipes, we have a frame of board made full of holes round about the bottom of our pipe that receives the water, for sluge or fine dirt it will do my engine no injury. Indeed, the clearer our water is in our boilers the better it is for our work; but for our receivers and their clacks you may clear them as you work it from stones, coal, ore, or any other annoyance, though hung in the very clack; for by emptying of one or both the receivers of their water, you cause the motion, either of suction or force, immediately to be so strong, as to clear and blow out all before it to the top of the pit; insomuch, that I have found filings of copper, large bits of metal, considerable quantities of coal and stone, delivered and thrown up with water out of my engine above sixty feet high. However, clear water is preferable before the dirty water in the work of mine engine.

_Miner_. But, dear sir, if sixty, seventy, or eighty feet be the determinate height for raising of water by your engine, how shall we use your engine in a mine or pit that requires water to be raised three times eighty feet, as you know some of our works do.

_Author_. I heartily thank you, sir, for this last proposal, because I have now an opportunity to acquaint you, that the force used in my engine is in a manner infinite and unlimited, and will raise your water five hundred or one thousand feet high, were any pit so deep; and that you could find us a way to procure strength enough to support such an immense weight, as a pillar of water a thousand feet high must certainly produce. However, to give you an answer, I must entreat you to give my engine as kind entertainment and fair quarter as you do to your engines now in use: for, I am sure, you are not ignorant of a custom used in very deep mines, (in several parts of England,) of raising their water by several lifts, from cistern to cistern, to a very great height, although some of their lifts may not be above twelve, sixteen, or twenty feet a lift at the most. And suppose that your engine now in use at twenty feet the lift, and my engine at sixty, seventy, or eighty feet, for at any of these lifts we raise a full bore of water with much ease, then one lift of my engine at sixty feet answers to three lifts of your engines at twenty feet, and also to four of your lifts at eighty feet, &c., which you may please to take for a sufficient answer to your last objection. I have known, in Cornwall, a work with three lifts, of about eighteen feet each lift, and carrying a three and a quarter inch bore, that cost forty-two shillings per diem, reckoning twenty-four hours the day, for labour, besides wear and tear of engines; each pump having four men working eight hours, at fourteenpence a man, and the men obliged to rest at least one-third part of that time.

_Miner_. You have, sir, hitherto given me undeniable answers to my former objections, for which I thank you; but I fancy I shall puzzle you, when I ask you how you will manage your engine to draw up our water, where the shafts are not direct, but turn and wind to and fro?

_Author_. Sir, this last question is so far from being any hardship put upon my engine, that no engine ever yet invented was so naturally adapted to work in these crooked shafts as mine is; for let the windings or turnings of the shafts be what they will, the perpendicular weight of water is all that my engine has to account for, and is the same as if it made the figure of a distiller’s worm, and went through the straightest pipe imaginable, except a little inconsiderable friction of the water against the side of the pipe that is crooked, more than is in the straight pipe, which is so small a matter, that a very nice judge would hardly be able to distinguish whether the crooked or straight pipe carried off most water in the working. For the flue that carries the smoke, experience sufficiently instructs you, that you may turn and wind it any way you please, and that such windings in their drawing most air do rather improve than prejudice your flue, as any one experienced in building of furnaces can inform you.

_Miner_. Well, sir, I find that our crooked shafts will not any way incommode your engine: but what think you of accommodating your engine to the service of the lead mines, whose shafts are many times so narrow, that it will be very difficult to get your engine down?

_Author_. I perceive, sir, you are yet much a stranger to the nature of my engine, which is so furnished with brass screws, and as strong as the very metal itself, that you may take it to pieces, and with ease put it together again fit to work in a few hours’ time; and so contrived, that where a man can well go down, there I can put down my engine in several pieces and fix them below, for the greatest boiler belonging to my engine is between twenty-four and thirty inches diameter, and may, if occasion require, be made yet much narrower and deeper. And that if it be difficult to bring the shaft of the mine to fit my engine, I can, with much ease, make my engine to fit the shaft of any mine.

_Miner_. But will not these brass valves that you speak of in your engine, speedily wear out and stop your work?

_Author_. No: they cannot fail me; because experience shows us, that brass valves improve, rather than grow worse, by twenty or thirty years use in any force-work, where constantly worked, and where they rise and fall twenty times oftener than my valves will do.

_Miner_. But what think you, sir, if you should meet with such corrosive water in some of our mines, as will, in a little time, eat through your copper vessels.

_Author_. Truly, sir, this question does a little startle me, because I never expected to meet any water of such a corrosive quality in any mine: and could I find out a mine, whose water abounds with such acid particles, as to destroy or injure the copper vessels of my engine, I would drain that mine for nothing but the water I shall take up; because the water would be more valuable than any ore (I believe) in England. And were there even a tenth part of aquafortis to nine-tenths of common water, which is impossible to suppose it should be, I say, such a water could have no effect on the coppers, were that water to lodge some time in the copper vessels, much less in passing through them with that celerity and rapid motion that always accompanies it.

_Miner_. But, sir, will not such a continual fire, as must be kept under your boilers, burn them out in two or three months’ time, and spoil the work of your engine?

_Author_. I can assure you they will not decay in some years, unless some fellow be hired or employed on purpose to do it. And should any villain be employed to burn, break, or destroy any of the engines now used in your works for raising of water, we are then on the same level with you in that point. But I will give you one reason why my engines will not easily decay, and I am sure that will go further with you than all the affirmation I can make. For, first of all, although a white heat will melt copper, and a red heat, and sudden cooling it again, will scale the copper, yet such a heat as is possible for it to have or suffer while water is in the boiler can have no ill effect, or cause any alteration in our copper. A friend of mine has coppers used in sugar boiling of twenty years’ standing. They may be a small matter worn with cleaning on the inside, whereas on the outside there does not appear the least visible decay: for as soon as the fire has thrown a thin coat of soot on the outside of the boiler, the flame has no other effect on it than to cause the water in it to boil.

_Miner_. But we have often combustible vapours in our mines, which taking fire from the candles used there, do, by a sudden explosion, destroy both the mine and the miner; and therefore I am afraid that the fire used in your engine will be very dangerous, and apt to kindle those combustibles more than our candles.