Appleton's dictionary of machines, mechanics, engine-work, and engineering (1869)
New York, Appleton · leaf 618
d< pend upon tin same principles, and are calculated by the same formulae as those given for the great lenses. In fixingthe focal distance and inclination of those subsidiary lenses, Fresnel was guided by a consideration of■•. for keeping them sufficiently high to prevent interference with the…
Mechanical engineering
Internet Archive · Gerstein Library, University of Toronto · Public Domain Mark 1.0. Free to use for anything.
