Lynde, Carleton John, b. 1872, Gilbert, Alfred C. (Alfred Carlton), 1884-1961 · New Haven, Conn. : A.C. Gilbert Co. · leaf 58
yourself? Turn the upper mirror until it looks backward(Fig. 81). Can you see back over your head, but is everything up-side down? Turn the upper mirror until it looks sidewise(Fig. 82).Can you see things, but are they turned on their sides? THE WHY OF THE PERISCOPE Now let us seewhy the image… … 56 GILBERT BOY ENGINEERING
Light · Scientific recreations
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