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."



Prov de 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.