quantity of water that comes from a pipe (hereafter mentioned) to
which it is to be fixed, and which may be fastened to any kind of
pump, provided it be so constructed, that the water shall have no
other means of escape than through the pipe. Pierce a number of small
holes through the globe, that all tend towards its centre, and annex
it to the pipe that communicates with the pump. The water that comes
from the pump, rushing with violence into the globe, will be forced
out at the holes, and form a very pleasing sphere of water.
_The Hydraulic Dancer._
Procure a little figure made of cork, which you may dress as your
fancy dictates. In this figure place a small hollow cone made of thin
leaf brass.
When the figure is placed on a jet d'eau, that plays in a
perpendicular direction, it will be suspended on the top of the water,
and perform a great variety of amusing motions.
If a hollow ball of very thin copper, of an inch diameter, be placed
on a similar jet, it will remain suspended, turning round, and
spreading the water all about it.
_A Person having put a Ring an one of his Fingers, to name the Person,
the Hand, the Finger, and the Joint on which it is placed._
Let a third person double the number of the order in which he stands
who has the ring, and add 5 to that number; then multiply that sum by
5, and to the product add 10. Let him next add 1 to the last number,
if the ring be on the right hand, and 2 if on the left, and multiply
the whole by 10: to the product of this he must add the number of the
finger, (counting the thumb as the first finger,) and multiply the
whole again by 10. Let him then add the number of the joint, and,
lastly, to the whole join 35.
He is then to tell you the amount of the whole, from which you are to
subtract 3535, and the remainder will consist of four figures; the
first of which will express the rank in which the person stands, the
second the hand, (number 1 signifying the right, and 2 the left,) the
third number the finger, and the fourth the joint.--For example:
Suppose the person who stands the third in order has put the ring upon
the second joint of the thumb of his left hand; then,
The double of the rank of the third person is 6
To which add 5
____
11
Multiply the sum by 5
____
55
To which add 10
And the number of the left hand 2
____
67
Which being multiplied by 10
____
670
To which add the number of the thumb 1
____
671
And multiply again by 10
____
6710
Then add the number of the joint 2
And lastly the number 35
____
6747
From which deducting 3535
____
The remainder is 3212
____
Of which, as we have said, the 3 denotes the third person, the 2 the
left hand, the 1 the thumb, and the last 2 the second joint.
_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 part where the two pieces are
joined together. The water rushing through the holes will form a very
pleasing water sun, or star.
_The Magical Cascade._
Procure a tin vessel, shaped like Fig. 5, about five inches high and
four in diameter, with a cover, C, closed at top. To the bottom of
this vessel, let the pipe D E be soldered. This pipe is to be ten
inches long, and half an inch in diameter, open at each end, and the
upper end must be above the water in the vessel. To the bottom also
fix five or six small tubes, F, about one-eighth of an inch in
diameter. By these pipes, the water in the vessel is to run slowly
out.
[Illustration: Fig. 5.]
Place this machine in a tin basin, G H, with a hole in the middle,
about a quarter of an inch in diameter. Fix to the tube D E, any sort
of ornament that will keep the machine firm on the basin, observing,
that these supports are sufficiently long to leave about a quarter of
an inch between the end of the tube and the orifice in the basin; and
let there be a vessel under the basin to catch the water that runs
out.
As the small pipes discharge more water into the basin than can run
out of the central orifice, the water will rise in the basin above the
lower end of the pipe, and prevent the air from getting into the
vessel, by which the water will cease to flow from the small pipes.
But as the water continues to flow from the basin, the air will have
liberty again to enter the vessel by the tube, and the water will
again flow from the small pipes, and alternately stop and flow, while
any water remains in the vessel.
As you can guess when the pipes will flow, and when they will stop,
you may so manage it, that they will appear to act by word of command.
_The illuminated Fountain, that plays when the Candles are lighted,
and stops when they are extinguished._
Provide two cylindrical vessels, A B and C D, as in Fig. 6. Connect
them by four tubes open at each end, as H I, &c., so that the air may
descend out of the higher into the lower vessel. To these tubes fix
candlesticks, and to the hollow cover, E F, of the lower vessel, fit a
tube, K, reaching almost to the bottom of the vessel. At G let there
be an aperture with a screw, whereby water may be poured into C D,
which, when filled, must be closed by the screw.
[Illustration: Fig. 6.]
When the candles are lighted, the air in the upper cover and
contiguous pipes will be thereby rarefied, and the jet from the small
tube, K, will begin to play: as the air becomes more rarefied, the
force of the jet will increase, and it will continue to play till the
water in the lower vessel is exhausted. As the motion of the jet is
caused by the heat of the candles, when they are extinguished the
fountain will stop.
_A Fountain which acts by the heat of the Sun._
In the annexed engraving, Fig. 7, G N S is a thin hollow globe of
copper, eighteen inches diameter, supported by a small inverted basin,
placed on a stand with four legs, A B C D, which have between them, at
the bottom, a basin of two feet diameter. Through the leg C passes a
concealed pipe, which comes from G, the bottom of the inside of the
globe. This pipe goes by H V, and joins the upright pipe _u_ I, to
make a jet, as I. The short pipe, _u_ I, which goes to the bottom, has
a valve at _u_, under the horizontal pipe H V, and another valve at T,
above that Horizontal pipe, under the cock at K. The use of this cock
is to keep the fountain from playing in the day, if you think proper.
The north pole N of the globe has a screw that opens a hole, whereby
water is poured into the globe.
[Illustration: Fig. 7.]
The machine being thus prepared, and the globe half filled with water,
put it in an open place, when the heat of the sun rarefying the air as
it heats the copper, the air will press strongly against the water,
which, coming down the pipe, will lift up the valve at V, and shut the
valve at u. The cock being opened, the water will spout out at I, and
continue to play a long while, if the sun shines.
_Inflammable Phosphorus._
Take the meal of flour of any vegetable, put it into an iron pan over
a moderate fire, and keep it stirring with an iron spoon till it
changes to a black powder; to one part of this add four parts of raw
alum. Make the whole into a fine powder; put it again into the iron
pan, and keep stirring it till it almost catches fire, to prevent its
forming into lumps, as it is apt to do when the alum melts; in which
case it must be broken again, stirred about, and accurately mixed with
the flour, till it emits no more fumes, and the whole appears a fine
black powder.
Put this powder in a clean dry phial with a narrow neck, filling it to
about one-third of the top. Then stop the mouth of the phial with
loose paper, so as to let the air pass freely through it, and leave
room for the fumes to come through the neck. Place the phial in a
crucible, encompassed on all sides with sand, so that it may not touch
any part of the crucible, but a considerable space everywhere left
between. The phial must be covered up with sand, leaving only a small
part bare, by which you can discern whether the powder is ignited. In
this state, the crucible is to be surrounded with coals, kindled
slowly till it is well heated on all sides, and then the fire is to be
raised, till the crucible and every thing in it is red-hot; keep it in
this state an hour; after this, the fire still burning as fiercely,
close up the orifice of the phial with wax, to exclude the air. Leave
it to cool, and you will find in it a black dusty coal formed of the
flour and alum.
Shake a small quantity of this out of the phial into the cool air, and
it will immediately take fire, but will not burn any thing. Keep the
bottle dry, as even the air will spoil it effectually.
_The Magical Mirrors._
Make two holes in the wainscot of a room, each a foot high and ten
inches wide, and about a foot distant from each other. Let these
apertures be about the height of a man's head, and in each of them
place a transparent glass in a frame, like a common mirror.
Behind the partition, and directly facing each aperture, place two
mirrors enclosed in the wainscot, in an angle of forty-five
degrees.[B] These mirrors are each to be eighteen inches square: and
all the space between them must be enclosed with pasteboard painted
black, and well closed, that no light can enter; let there be also two
curtains to cover them, which you may draw aside at pleasure.
When a person looks into one of these fictitious mirrors, instead of
seeing his own face he will see the object that is in front of the
other; thus, if two persons stand at the same time before these
mirrors, instead of each seeing himself; they will reciprocally see
each other.
There should be a sconce with a lighted candle, placed on each side of
the two glasses in the wainscot, to enlighten the faces of the persons
who look in them, or the experiment will not have so remarkable an
effect.
[B] That is, half-way between a line drawn perpendicularly to
the ground and its surface.
_To cause a brilliant Explosion under Water._
Drop a piece of phosphorus, the size of a pea, into a tumbler of hot
water; and, from a bladder furnished with a stop-cock, force a stream
of oxygen directly upon it. This will afford a most brilliant
combustion under water.
_Fulminating Mercury._
Dissolve 100 grains of mercury by heat, in an ounce and a half of
nitric acid. This solution being poured cold upon two measured ounces
of alcohol previously introduced into any convenient glass vessel, a
moderate heat is to be applied, till effervescence is excited. A white
fume then begins to appear on the surface of the liquor, and the
powder will be gradually precipitated when the action ceases. The
precipitate is to be immediately collected on a filter, well washed
with distilled water, and cautiously dried in a heat not exceeding
that of a water-bath. Washing the powder immediately is material,
because it is liable to the re-action of the nitric acid; and, while
any of the acid adheres to it, it is very subject to the action of
light. From 100 grains of mercury, about 130 of the powder are
obtained.
This powder, when struck on an anvil with a hammer, explodes with a
sharp stunning noise, and with such force as to indent both hammer and
anvil. Three or four grains are sufficient for one experiment.
_The Iron Tree._
Dissolve iron filings in aqua fortis, moderately concentrated, till
the acid is saturated; then add to it gradually, a solution of fixed
alkali, (commonly called oil of tartar per deliquum.) A strong
effervescence will ensue, and the iron, instead of falling to the
bottom of the vessel, will afterwards rise so as to cover the sides,
forming a multitude of ramifications heaped one upon the other, which
will sometimes pass over the edge of the vessel, and extend themselves
on the outside, with all the appearance of a plant.
_To make any Number divisible by Nine, by adding a Figure to it._
If (for example) the number named be 72,857, you tell the person who
names it to place the number 7 between any two figures of that sum,
and it will be divisible by 9; for if any number be multiplied by 9,
the sum of the figures of the product will be either 9, or a number
divisible by 9.
_Arithmetical Squares._
An arithmetical magical square consists of numbers so disposed in
parallel and equal lines, that the sum of each, taken any way of the
square, amounts to the same.
Any five of these sums taken in a right line make 65. You will observe
that five numbers in the diagonals A to D, and B to C, of the magical
square, answer to the ranks E to F, and G to H, in the natural square,
and that 13 is the centre number of both squares.
_A Natural Square._ _A Magical Square._
A G B A B
+--+--+--+--+--+ +--+--+--+--+--+
| 1| 2| 3| 4| 5| |11|24| 7|20| 3|
+--+--+--+--+--+ +--+--+--+--+--+
| 6| 7| 8| 9|10| | 4|12|25| 8|16|
+--+--+--+--+--+ +--+--+--+--+--+
E |11|12|13|14|15| F |17| 5|13|21| 9|
+--+--+--+--+--+ +--+--+--+--+--+
|16|17|18|19|20| |10|18| 1|14|22|
+--+--+--+--+--+ +--+--+--+--+--+
|21|22|23|24|25| |23| 6|19| 2|15|
+--+--+--+--+--+ +--+--+--+--+--+
C H D C D
To form a magical square, first transpose the two ranks in the natural
square to the diagonals of the magical square; then place the number 1
under the central number 13, and the number 2 in the next diagonal
downward. The number 3 should be placed in the same diagonal line; but
as there is no room in the square, you are to place it in that part it
would occupy if another square were placed under this. For the same
reason, the number 4, by following the diagonal direction, falling out
of the square, it is to be put into the part it would hold in another
square, placed by the side of this. You then proceed to numbers 5 and
6, still descending; but as the place 6 should hold is already filled,
you then go back to the diagonal, and consequently place the 6 in the
second place under the 5, so that there may remain an empty space
between the two numbers. The same rule is to observed, whenever you
find a space already filled.
You proceed in this manner to fill all the empty cases in the angle
where the 15 is placed: and as there is no space for the 16 in the
same diagonal, descending, you must place it in the part it would hold
in another square, and continue the same plan till all the spaces are
filled. This method will serve equally for all sorts of arithmetical
progressions composed of odd numbers; even numbers being too
complicated to afford any amusement.
_To find the Difference between two Numbers, the greatest of which is
unknown._
Take as many nines as there are figures in the smallest number, and
subtract that sum from the number of nines. Let another person add
that difference to the largest number, and, taking away the first
figure of the amount, add it to the last figure, and that sum will be
the difference of the two numbers.
For example: Robert, who is 22, tells George, who is older, that he
can discover the difference of their ages; he therefore privately
deducts 22 from 99, and the difference, which is 77, he tells George
to add to his age, and to take away the first figure from the amount,
and add it to the last figure, and that last sum will be the
difference of their ages. Thus, the difference between
Robert's age and 99, is 77
To which George adding his age 35
----
The sum will be 112
----
12
1
----
Then by taking away the first figure, 1, }
and adding it to the last figure, 2, } 13
the sum is }
Which added to Robert's age 22
----
Gives George's age, which is 35
_The Boundless Prospect._
Take a square box, about six inches long and twelve high, or of any
other proportionate dimensions. Cover the inside with four flat pieces
of looking-glass placed perpendicular to the bottom of the box. Place
at the bottom any objects you please, as a piece of fortification, a
castle, tents, soldiers, &c. On the top, place a frame of glass shaped
like the bottom of a pyramid, as in Fig. 8, and so formed as to fit on
the box like a cover. The four sides of this cover are to be composed
of ground glass, or covered inside with gauze, so that the light may
enter, and yet the inside be invisible, except at the top, which must
be covered with transparent glass: when you look through this glass,
the inside will present a pleasing prospect of a boundless extent;
and, if managed with care, will afford a deal of amusement.
[Illustration: Fig. 8.]
_To set Fire to a combustible Body by Reflection._
Place two concave mirrors at about twelve feet distance from each
other, and let the axis of each be in the same line. In the focus of
one of them place a live coal, and in the focus of the other some
gunpowder. With a pair of strong bellows keep blowing the coal, and
notwithstanding the distance between them, the powder will presently
take fire.
The mirror may be either made of glass, metal, or pasteboard gilt.
_To find the Number of Changes that may be rung on Twelve Bells._
Multiply the numbers from 1 to 12 continually into each other, as
follow: and the last product will give the number required.
1
2
--
2
3
--
6
4
--
24
5
----
120
6
----
720
7
-----
5,040
8
------
40,320
9
-------
362,880
10
---------
3,628,800
11
----------
39,916,800
12
-----------
479,001,600
_To find how many square Yards it would require to write all the
Changes of the Twenty-four Letters of the Alphabet, written so small,
that each Letter should not occupy more than the hundredth part of a
square Inch._
By adopting the plan of the preceding article, the changes of the
twenty-four letters will be found to be
62,044,840,173,323,943,936,000.
Now, the inches in a square yard being 1,296, that number multiplied
by 100 gives 129,600, which is the number of letters each square yard
will contain; therefore, if we divide the above row of figures,
(the number of changes,) by 129,600, the quotient, which is
478,741,050,720,092,160, will be the number of yards required to
contain the above mentioned number of changes. But as all the 24
letters are contained in every permutation, it will require a space
24 times as large, _viz._,
11,849,785,210,282,211,840.
Now, as the surface of the whole globe only contains
617,197,435,008,000 square yards, it would require a surface 18,620
times as large as the earth to contain them.
_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; and instead of the
water appearing, as it really is, at the bottom of the bottle, the
bottom will be empty, and the water seen at the top.
If the bottle be suspended with the neck downwards, it will be
reflected in its natural position, and the water at the bottom,
although in reality it is inverted, and fills the neck; leaving the
bottom vacant. While the bottle is in this position, uncork it, and
let the water run gradually out: it will appear, that while the real
bottle is emptying, the reflected one is filling. Care must be taken
that the bottle is not more than half or three parts full, and that no
other liquid is used but water, as in either of these cases the
illusion ceases.
_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 the box against a window, on
which the sun's rays fall direct. The rest of the window should be
closed up, that no light may enter.
Next provide several sheets of stiff paper, blacked on one side. On
these papers cut out such figures as your fancy may dictate; place
them alternately in the grooves of the box, with their blacked sides
towards you, and look at them through a large and clear glass prism;
and if the light be strong, they will appear painted with the most
lively colours. If you cut on one of these papers the form of a
rainbow, about three-quarters of an inch wide, you will have a very
good representation of the natural one.
For greater convenience, the prism may be placed on a stand on the
table, made to turn round on an axis.
_The Artificial Rainbow._
Opposite a window into which the sun shines direct suspend a glass
globe, filled with clean water, by means of a string that runs over a
pulley, so that the sun's rays may fall on it. Then drawing the globe
gradually up, you will observe, when it comes to a certain height, and
by placing yourself in a proper situation, a purple colour in the
glass; and by drawing it up gradually higher, the other prismatic
colours, blue, green, yellow, and red, will successively appear; after
which, the colours will disappear, till the globe is raised to about
fifty degrees, when they will again appear, but in an inverted order,
the red appearing first, and the blue or violet last; on raising the
globe a little higher, they will totally vanish.
_The AEolipiles._
The aeolipile is a small hollow globe of brass, or other metal, in
which a slender neck or pipe is inserted. This ball, when made
red-hot, is cast into a vessel of water, which will rush into its
cavity, then almost void of air. The ball being then set on the fire,
the water, by the rarefaction of the internal air, will be forced out
in steam by fits, with great violence, and with strange noise.
If to the necks of two or more of these balls, there be fitted those
calls that are used by fowlers and hunters, and the balls placed on
the fire, the steam rushing from them will make such a horrible noise,
that it will astonish any person who is ignorant of the contrivance.
_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 care that the end of the tube
that is next the ear of the one head, be considerably larger than that
end which comes to the mouth of the other.
Now, when a person speaks quite low into the ear of one bust, the
sound is reverberated through the length of the tube, and will be
distinctly heard by any one placing his ear to the mouth of the other.
It is not necessary that the tube should come to the lips of the bust.
If there be two tubes, one going to the ear, and the other to the
mouth of each head, two persons may converse together, by whispers,
without the knowledge of any person who may stand in the middle of the
room.
_The Inanimate Oracle._
Place a bust on a pedestal in the corner of a room, and let there be
two tubes, as in the preceding article, one to go from the mouth, and
the other from the ear, through the pedestal and the floor to an under
apartment; there may be also wires, that go from the under jaw and the
eyes of the bust, by which they may be easily moved.
A person being placed in the room underneath, and applying his ear to
one of the tubes at a signal given, will hear any question asked, and
can immediately reply, by applying his mouth to the tube which
communicates below, at the same time moving the eyes by the wire, to
accompany his speech.
_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 that takes a toothed
wheel at the end of the barrel. To one end of this catch join a wire,
at the end of which is a flat circle of cork, of the same dimensions
with the inside of a glass tube, in which it is to rise and fall. This
tube must communicate with a reservoir that goes across the front part
of the bottom of the case, which is to be filled with spirits, such as
is used in thermometers.
This case being placed in the sun, the spirits will be rarefied by the
heat, and, rising in the tube, will lift up the catch or trigger, and
set the organ in play; which will continue as long as it is kept in
the sun; for the spirits cannot run out of the tube, that part of the
catch to which the circle is fixed being prevented from rising beyond
a certain point, by a check placed over it. Care must be taken to
remove the machine out of the sun before the organ runs down, that its
stopping may be evidently affected by the cold.
In winter it will perform when placed before the fire.
CURIOUS EXPERIMENTS WITH THE MAGIC LANTERN.