Perhaps some one in the company has made use of the saying that he “can
see as far through a millstone as anybody.”
Eagerly espouse his cause, and declare him, indeed, gifted with
preternatural vision, as you will prove to him by your magic spyglass.
A box is made with two upright extensions, in which are placed the tubes
of telescopes, with plain glass eyepieces. A A A A are plane mirrors,
set all at an angle of 45 degrees, so that any one looking in at either
end, sees whatever is visible at the other extremity.
[Illustration: Fig. 137.]