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 of glass, covered on the

inside with fine paper.



Let a person write on a slip of paper, putting your memorandum book

under it, as in the last amusement; then ive him the little box, and

let him put what he has written into it. In the mean time you put the

memorandum book into the press, where the perspective is already

placed. Your assistant then takes the paper out of the book, and puts

it at the bottom of the perspective; which you presently take out of

the press, and direct the person to put the little box that contains

the paper under it. You then look in at the top of the perspective,

and feigning to see through the top of the box, you read what is

written on the paper at the bottom of the perspective.



With this perspective box you may perform another amusement, which is,

by having in a bag twelve or more ivory counters, numbered, which you

show to the company, that they may see all the numbers are different.

You tell a person to draw any one of them, and keep it close in his

hand. You then put the bag in the press, when your assistant examines

the counters, and sees which is wanting, and puts another of the same

number at the bottom of the perspective, which you then take out, and

placing the person's hand close to it, look in at the top, and

pretending to see through his hand, you name the number on the counter

in it.