The Diagonal Opera Glass
By the diagonal position of a plane mirror, a curious opera-glass is
constructed, by which any person may be viewed in a theatre or public
company without knowing it. It consists only in placing a concave
glass near the plane mirror, in the end of a short round tube, and a
convex glass in a hole in the side of the tube, then holding the end
of the tube with the glass to the eye, all objects next to the hole in
the side will be reflected so as to appear in a direct line forward,
or in a position at right angles to the person's situation who is
looked at. Plane glasses, instead of a convex and concave, may be
used; in this case the size of the object will not be increased, but
it will appear brighter.
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The Cameleon Spirit
Put into a decanter volatile spirit, in which you have dissolved copper filings, and it will produce a fine blue. If the bottle be stopped, the colour will disappear; but when unstopped, it will return. This experiment may be often repeated. ... The Candle Lighted By Electricity
Charge a small coated phial, whose knob is bent outwards so as to hang a little over the body of the phial; then wrap some loose cotton over the extremity of a long brass pin or wire, so as to stick moderately fast to its substance. Next roll this e... The Card Changed By Word Of Command
You must have two cards of the same sort in the pack, (say the king of spades.) Place one next the bottom card, (say seven of hearts,) and the other at top. Shuffle the cards without displacing those three, and show a person that the bottom card is ... The Card Discovered By The Touch Or Smell
You offer the long card, or any other that you know, and as the person who has drawn it holds it in his hand, you pretend to feel the pips or figure on the under side, by your fore-finger; or you sagaciously smell to it, and then pronounce what card... The Card Discovered Under The Handkerchief
Let a person draw any card from the rest, and put it in the middle of the pack; you make the pass at that place, and the card will consequently be at top; then placing the pack on the table, cover it with a handkerchief; and, putting your hand under... The Card Found Out By The Point Of The Sword
When a card has been drawn, you place it under the long card, and by shuffling them dexterously, you bring it to the top of the pack. Then lay or throw the pack on the ground, observing where the top card lies. A handkerchief is then bound round you... The Card Hit Upon By The Guess
Spread part of the pack before a person, in such way that only one court card is visible; and so arrange it, that it shall appear the most prominent and striking card. You desire him to think on one; and observe if he fix his eye on the court card. ... The Card In The Egg
Take a card, the same as your long card, and, rolling it up very close, put it in an egg, by making a hole as small as possible, and which you are to fill up carefully with white wax. You then offer the long card to be drawn, and when it is replaced... The Card In The Mirror
Provide a mirror, either round or oval, the frame of which must be at least as wide as a card, and the glass must be wider than the distance between the frame, by at least the width of a card. The glass in the middle must be made to move in two groo... The Card In The Opera Glass
Procure an opera-glass, two inches and a half long; the tube to be made of ivory, so thin that it may appear transparent. Place it in a magnifying glass, of such a power, and at such a distance, that a card, three-quarters of an inch long, may appea... The Card In The Pocket-book
A confederate is previously to know the card you have taken from the pack, and put into your pocket-book. You then present the pack to him, and desire him to fix on a card, (which we will suppose to be the queen of diamonds,) and place the pack on t... The Card In The Ring
Get a ring, made of any metal, in which is set a large transparent stone or piece of glass, to the bottom of which is fastened a small piece of black silk; under the silk is to be the figure of a small card; and the silk must be so constructed that ... The Cemented Bladder
Tie the neck of the bladder to a stop-cock, which is to be screwed to the plate of the pump, and the air exhausted from the bladder; then turn the stop-cock, to prevent the re-entrance of the air, and unscrew the whole from the pump. The bladder wil... The Changeable Rose
Take a common full-blown rose, and, having thrown a little sulphur finely pounded into a chafing-dish with coals, expose the rose to the vapour. By this process the rose will become whitish; but if it be afterwards held some time in water, it will r... The Convertible Aces
On the ace of spades fix, with soap, a heart, and on the ace of hearts a spade, in such a manner that they will easily slip off. Show these two aces to the company; then, taking the ace of spades, you desire a person to put his foot upon it, and a... The Convertible Cards
To perform this amusement you must observe, that there are several letters which may be changed into others, without any appearance of ... The Cup Of Tantalus
You place a cup of any sort of metal on a stool of baked wood or a cake of wax. Fill it to the brim with any liquor; let it communicate with the branch by a small chain; and when it is moderately electrified, desire a person to taste the liquor, wit... The Deforming Mirrors
If a person look in a concave mirror placed perpendicularly to another, (that is, supposing one mirror to be laid on the floor, and the other attached to the ceiling,) his face will appear entirely deformed. If the mirror be a little inclined, so as... The Diagonal Opera Glass
By the diagonal position of a plane mirror, a curious opera-glass is constructed, by which any person may be viewed in a theatre or public company without knowing it. It consists only in placing a concave glass near the plane mirror, in the end of a... The Distorting Mirror
Opticians sometimes grind a glass mirror concave in one direction only, or longitudinally; it is in fact a concave portion of a cylinder, the breadth of which may be considered that of the mirror. A person looking at his face in this mirror, in the ... The Divining Card
Provide a pack in which there is a long card; open it at that part where the long card is, and present the pack to a person in such a manner that he will naturally draw that card. You then tell him to put it into any part of the pack, and shuffle th... The Divining Perspective Glass
Procure a small perspective-glass, wide enough, where the object-glass is placed, to hold the following table: +-------+--------+--------+ 1,131 10,132 19,133 2,231 11,232 20,233 3,331 12,332 21,333 +-------+--------+-----... The Dodecahedron
So called because it nearly represents a twelve-sided figure, is made thus: First have a ball turned out of some hard wood, 14 inches diameter; divide its surface into 14 equal parts, from which bore holes one inch and a half diameter, perpendicular... The Electric Aurora Borealis
Make a Torricellian vacuum[G] in a glass tube, about three feet long, and hermetically sealed.[H] Let one end of this tube be held in the hand, and the other applied to the conductor; and immediately the whole tube will be illuminated from one end; ... The Electric Ball
Provide a ball of cork about three-quarters of an inch in diameter, hollowed out in the internal part by cutting it in two hemispheres, scooping out the inside, and then joining them together with paste. Having attached this to a silk thread between... The Electric Balloon
Two balloons, made of the allantoides of a calf, are to be filled with hydrogen gas, of which each contains about two cubic feet. To each of these is to be suspended, by a silken thread about eight feet long, such a weight as is just sufficient to p... The Electric Explosion
Take a card, a quire of paper, or the cover of a book; and keep it close to the outside coating of a charged jar: put one knob of the discharging-rod upon the card, quire of paper, &c., so that, between the knob and coating of the jar, the thickness... The Electric Kite
Make a small cross of two light strips of cedar, the arms so long as to reach to the four corners of a large thin silk handkerchief, when extended; tie the corners of the handkerchief to the extremities of the cross; and you have the body of the kit... The Electric Sparks
When the prime conductor is situated in its proper place, and electrified by whirling the cylinder, if a metallic wire, with a ball at its extremity, or the knuckle or a finger be presented to the prime conductor, a spark will be seen to issue betwe... The Electrical Fountain
Suspend a vessel of water from the middle of the brass arch, and place in the vessel a small tube. The water will be one continued stream; and if the electrification be strong, a number of streams will issue, in form of a cone, the top of which will... The Electrical Orrery
By the motion of circulating points, we may in some measure imitate ... The Electrified Ball
Place an ivory ball on the prime conductor of the machine, and take a strong spark, or send the charge of a Leyden phial through its centre, and the ball will appear perfectly luminous; but if the charge be not sent through the centre, it will pass ... The Electrified Camphor
A beautiful experiment of the same nature is made with camphor. A spoon holding a piece of lighted camphor is made to communicate with an electrified body, as the prime conductor of a machine; while the conductor continues electrified by keeping the... The Electrified Cotton
Take a small lock of cotton, extended in every direction as much as can conveniently be done, and by a linen thread about five or six inches long, or by a thread drawn out of the same cotton, tie it to the end of the prime conductor; then set the ma... The Enchanted Bottle
Fill a glass bottle with water to the beginning of the neck; leave the neck empty, and cork it. Suspend this bottle opposite a concave mirror, and beyond its focus, that it may appear reversed. Place yourself still further distant from the bottle; a... The Enchanted Palace
On the six-sided plane A B C D E F, Fig. 21, draw six semi-diameters; and on each of these place perpendicularly two plane mirrors, which must join exactly at the centre, and which, placed back to back, must be as thin as possible. Decorate the exte...