Appleton's dictionary of machines, mechanics, engine-work, and engineering (1869)
New York, Appleton · leaf 616
irrtijm* … I central .h-k of the lent, which is employed in lights of tl. about il inches in diameter; and the annulain breadth, as the} recede from the axis, from Ith ol . u ill,in certain limit*, a mui part of Vo,.. n. eio SEA-LIGHTS. the lens should be much thicker than the rest, as well for the purpose of…
Mechanical engineering
Internet Archive · Gerstein Library, University of Toronto · Public Domain Mark 1.0. Free to use for anything.
