The Magic Verse

The eight words which compose this Latin verse,

"Tot sunt tibi dote, quot coeli sidera, virgo,"[F]

being privately placed in any one of the different combinations of
which they are susceptible, and which are 40,320 in number, to tell
the order in which they are placed.

[F] "Thy charms, O, Virgin! are as numerous as the stars of
heaven."

Provide a box that shuts with hinges, and is eight inches long, three
wide, and half an inch deep, Fig. 17. Have eight pieces of wood, about
one-third of an inch thick, two inches long, and one and a half wide,
which will therefore, when placed close together, exactly fill the
box. In each of these pieces or tablets place a magnetic bar, with
their poles, as is expressed in Fig. 18. The bars being covered over,
write on each of the tablets, in the order they then stand, one of the
words of the foregoing Latin verse.

On a very thin board of the same dimensions with the box, draw the
eight circles, Fig. 19, A B C D E F G H, whose centres should be
exactly over those of the eight tablets in the box, when the board is
placed upon it. Divide each of those circles into eight parts, as in
the figure, and in each of those divisions write one of the words of
the Latin verse, and in the precise order expressed in the plate, so
that when the board is placed over the box, the eight touched needles
placed at the centre of the circles may be regulated by the poles of
the bars in the box, and consequently the word that the needle points
to in the circle will be the same with that inscribed on the tablet.
Cover the board with a glass, to prevent the needles from rising off
their pivots, as is done in the sea-compass.

Over the board place four plates of glass, I L M N, Fig. 17, which
will give the machine the figure of a truncated pyramid, of eight
inches high. Cover it with a glass, or rather a board, in which are
placed two lenses, O, of eight inches focus, and distant from each
other about half an inch. Line the four plates of glass that compose
the sides with very thin paper, that will admit the light, and at the
same time prevent the company from seeing the circles on the board.

These preparations being made, you give the box to any one, and tell
him to place the tablets, on which the words are written privately, in
what position he thinks proper, then to close the box, and, if he
please, to wrap it up in paper, seal it, and give it to you. Then
placing the board with the pyramid upon it, you immediately tell him
the order in which the tablets are placed, by reading the words to
which the needles on the circles point.

INTERESTING EXPERIMENTS WITH THE AIR-PUMP.

We shall not occupy the time of our readers by describing the form and
nature of the air-pump; since those persons whose circumstances will
enable them to have it, can purchase it properly made at an
optician's, at less expense, and with far less trouble, than they can
construct, or cause it to be constructed, themselves.

Next: Bottles Broken By Air
Previous: The Magnetic Orrery