Lessons in astronomy including uranography. A brief intoductory course without mathematics (1896)
Young, Charles A. (Charles Augustus), 1834-1908 · Boston, London, Ginn and company · leaf 328
n of theobservations is taken as giv-ing the moment when the star crossed the middle wire. A delicate spirit-level, to be placedon the pivots and test the horizon-tally of the axis, is an indispensableaccessory. So far as the theory of the instru-ment is concerned, a graduated circleis not… … Fig. i - The Transit Instrument.
Astronomy
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
