The Pressure Of Water
The pressure of water may be known to every one who will only take the
trouble to look at the cock of a water-butt when turned: if the tub or
cistern be full, the water runs with much greater velocity through
the cock, and a vessel will be filled from it in a shorter time than
when it is only half-full, although the cock, in both cases, is
equally replete with the fluid during the time the vessel is filling.
From this also is understood, how a hole or leak, near the keel of a
ship, admits the water much quicker, and with greater violence, than
one of the same size near what the mariners call the water's edge.
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The Mercurial Shower
Cement a piece of wood into the lower part of the neck of an open receiver, and pour mercury over it. After a few strokes of the pump, the pressure of the air on the mercury will force it through the pores of the wood in the form of a beautiful show... The Mercurial Wand
Take a piece of stick, cut it even at each end with a penknife, and immerse it in a vessel of mercury. When the air is pumped out of the receiver, it will at the same time come out of the pores of the wood, through the mercury, as will be visible at... The Metamorphosed Cards
In the middle of a pack place a card that is something wider than the rest, which we will suppose to be the knave of spades, under which place the seven of diamonds, and under that the ten of clubs. On the top of the pack put cards similar to these,... The Miraculous Luminaries
You must previously prepare the following phosphorus: Calcine common oyster-shells, by burning them in the fire for half an hour; then reduce them to powder; of the clearest of which take three parts, and of flowers of sulphur one part; put the mixt... The Miraculous Portrait
Get a large print (suppose of the king) with a frame and glass. Cut the print out at about two inches from the frame all round; then with thin paste fix the border that is left on the inside of the glass, pressing it smooth and close; fill up the va... The Mysterious Watch
You desire any person to lend you his watch, and ask him if it will go when laid on the table. He will, no doubt, say it will; in which case, you place it over the end of the magnet, and it will presently stop. You then mark the precise spot where y... The Mysterious Writing
Write on a piece of paper with common ink any question; then underneath it write the answer either in invisible silver ink, or the invisible green ink, made with zaffre and aqua regia, described in pages 24 and 25. You give this paper to your fri... The Numerical Cards
Let the long card be the sixteenth in the pack of piquet cards. Take ten or twelve cards from the top of the pack, and, spreading them on the table, desire a person to think on any one of them, and to observe the number it is from the first card. Ma... The Opaque Box Made Transparent
Make a box three or four inches long, and two or three wide, and have a sort of perspective-glass, the bottom of which is the same size with the box, and slides out, that you may privately place a paper on it. The sides of this perspective are to be... The Oracular Mirror
Provide a round mirror of about three inches in diameter and whose frame is an inch wide. Line the under part of the frame, in which holes are to be cut, with very thin glass; behind this glass let a mirror of about two inches diameter be placed, wh... The Penetrative Guinea
Provide a large tin box, of the size of a large snuff-box, and in this place eight other boxes, which will go easily into each other, and let the least of them be of a size to hold a guinea. Each of these boxes should shut with a hinge, and to the l... The Perspective Mirror
Provide a box, A B C D, Fig. 24, of about two feet long, 15 inches wide, and 12 inches high. At the end A C, place the concave mirror, the focus of whose parallel rays is 18 inches from the reflecting surface. At I L place a pasteboard, blacked, in ... The Phantom
You inform a person that at a certain hour, and in a certain place, he shall see the apparition of a deceased friend, (whose portrait you possess.) In order to produce this phantom, there must be a door which opens into an apartment to which there i... The Phial Of The Four Elements
Take a phial, six or seven inches long, and about three quarters of an inch in diameter. In this phial put, first, glass coarsely powdered; secondly, oil of tartar per deliquum; thirdly, tincture of salt of tartar; and lastly, distilled rock oil. ... The Philosophical Candle
Provide a bladder, into the orifice of which is inserted a metal tube, some inches in length, that can be adapted to the neck of a bottle, containing the same mixture as in the last experiment. Having suffered the atmospheric air to be expelled from... The Power Of Water
Let a strong small iron tube of twenty feet in height be inserted into the bung-hole of a cask, and the aperture round so strongly closed, that it shall be water-tight; pour water into the cask till it is full, through the pipe; also continue fillin... The Power Of Water When Reduced To Vapour By Heat
Whatever force water may have while its parts remain together, is nothing, if compared to the almost incredible power with which its parts are endued, when they are reduced to vapour by heat. Those steams which we see rising from the surface of boil... The Pressure Of Water
The pressure of water may be known to every one who will only take the trouble to look at the cock of a water-butt when turned: if the tub or cistern be full, the water runs with much greater velocity through the cock, and a vessel will be filled fr... The Restored Flowers
Make a bouquet of artificial flowers; the leaves should be formed of parchment. Dip the roses in the red invisible ink, the jonquilles in the yellow, the pinks in the violet, and the leaves in the green ink. They will all appear white; and you show ... The Self-moving Wheel
Take a circle of tin, about ten inches in diameter, or of any other size that will go into the receiver, and to its circumference fix a number of tin vanes, each about an inch square. Let this wheel be placed between two upright pieces on an axis, w... The Self-moving Wheel
The self-moving wheel is made of a thin round plate of window-glass, seventeen inches in diameter, well gilt on both sides, to within two inches of the circumference. Two small hemispheres of wood are then fixed with cement, to the middle of the upp... The Silver Tree
Dissolve an ounce of fine silver in three ounces of strong aqua fortis, in a glass bottle. When the silver is dissolved; pour the aqua fortis into another glass vessel, (a decanter will be best,) with seven or eight ounces of mercury, to which add a... The Solar Concerto
In a large case, similar to what is used for dials and spring clocks, the front of which, or at least the lower part, must be of glass, covered on the inside with gauze, place a barrel organ, which when wound up is prevented from playing by a catch ... The Solar Magic Lantern
Make a box, a foot high, eighteen inches wide, and about three inches deep. Two of the opposite sides of this box must be quite open, and in each of the other sides let there be a groove wide enough to admit a stiff paper or pasteboard. You fasten t... The Sublimated Tree
Into a large glass jar inverted upon a flat brick tile, and containing near its top a branch of fresh rosemary, or any other such shrub, moistened with water, introduce a flat thick piece of heated iron, on which place some gum benzoin, in gross pow... The Talking Busts
Procure two busts of plaster of Paris; place them on pedestals, on the opposite sides of the room. Let a thin tube, of an inch diameter, pass from the ear of one head through the pedestal, under the floor, and go up to the mouth of the other; taking... The Ten Duplicates
Select any twenty cards; let any person shuffle them; lay them by pairs on the board, without looking at them. You next desire several persons, (as many persons as there are pairs on the table,) each to look at different pairs and remember what card... The Three Magical Parties
Offer the long card to a person, that he may draw it, and replace it in any part of the pack he pleases. Make the pass, and bring that card to the top. Next divide the pack in three parcels, putting the long card in the middle heap. You then ask the... The Transmuted Cards
In a common pack of cards let the ace of hearts and nine of spades be something larger than the rest. With the juice of lemon draw over the ace of hearts a spade, large enough to cover it entirely, and on each side draw four other spades. Present... The Transposable Pieces
Take two guineas and two shillings, and grind part of them away, on one side only, so that they may be but half the common thickness; and observe, that they must be quite thin at the edge; then rivet a guinea and a shilling together. Lay one of thes... The Travelling Of Light
Light travels at the rate of a hundred and fifty thousand miles in a single second; and it is seven minutes in passing from the sun to the earth, which is nearly a distance of seventy millions of miles. Such is the rapidity with which these rays dar... The Travelling Of Sound Experimentally Proved
There is probably no substance which is not in some measure a conductor of sound; but sound is much enfeebled by passing from one medium to another. If a man, stopping one of his ears with his finger, stop the other also by pressing it against the e... The Unconscious Incendiary
Let a person stand upon a stool made of baked wood, or upon a cake of wax, and hold a chain which communicates with the branch. On turning the wheel he will become electrified; his whole body forming part of the prime conductor; and he will emit spa... The Water Sun
Provide two portions of a hollow sphere, that are very shallow; join them together in such a manner that the hollow between them be very narrow. Fix them vertically to a pipe from whence a jet proceeds. Bore a number of small holes all around that p...