The book of stars; being a simple explanation of the stars and their uses to boy life, written to conform to the tests of the Boy scouts (1915)
Collins, A. Frederick (Archie Frederick), 1869- · New York, D. Appleton and company · leaf 157
> 1 ?*r>/ ^ CARDBOARD TUBE … Fig. 150.—Cross Section of Pinhole Telescope. The disk must be glued in the tube so that no light can leakaround the edge. If, now, you look at the Sun through the pinhole telescope, asshown in Fig. 150, you will get a better view of it thanif you look at it through a pinhole in the cardboard…
Astronomy · Stars
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
![An illustration from L'optique divisée en trois livres : ou, l'On démontre d'une maniere aisée tout ce qui regarde 1. la propagation & les proprietez de la lumiere. 2. La vision. 3. La figure & la disposition des verres qui servent à la perfefectionner [sic] (1682)](https://img.insideoutlibrary.com/img/200/ia-loptiquedivise00ango-274-29.webp)
