London : Longman, Rees, Orme, Brown, Green, and Longman · leaf 244
turaleffect, let a spectrometer be made as in the diagram,Jig. 84. Let a conic front, expanding 60°, be con-structed with a square frame (a b c d), attachedto the base of the cone. On elevating or depress-ing the head, the frame or plane of the picturewill always contain the objects to be…
Architecture
Internet Archive · Public Domain Mark 1.0. Free to use for anything.
