Micrographia : containing practical essays on reflecting, solar, oxy-hydrogen gas microscopes; micrometers; eye-pieces, &c. &c. (1837)
Goring, C. R., 1792-1840, Pritchard, Andrew, 1804-1882, joint author · London : Whitaker and Co. · leaf 193
r determining how far any combinationof lenses is free from chromatic dispersion, are amply detailedin the Microscopic Cabinet, p. 200 : see also Test Objects,chap 16. III. The third defect, the aberration of the oblique pencilsof rays, will be better explained by referring to Fig. IV.,where B… … spherical figure of the lens, the extreme or marginal raysof the pencil will undergo greater refraction than those repre-sented by a a, nearly coinciding with the axis of the pencil,and will meet at m, the focus of marginal rays, whilst thosenear the axis of the pencil will proceed on to c, the…
Microscopy
Internet Archive · Medical Heritage Library · Public Domain Mark 1.0. Free to use for anything.
