Guy's elements of astronomy, and an abridgement of Keith's New treatise on the use of the globes (1832)
Guy, Joseph. [from old catalog], Keith, Thomas, 1759-1824. A new treatise on the use of the globes. [from old catalog] · Philadelphia, Key, Mielke & Biddle · leaf 122
<Vf. Jieluxrntiic and Geocentric Lonoinuie … UMBRA AND PENUMBRA, IN ECLirSES. 83 penumbra, P U the line described by the centres ofthe moons umbra and penumbra at the earth; N themoons node; E the earths centre; p n the moonspenumbra; u the umbra. Then in the first position,the penumbra^ n just passes by the earth, without fall-ing upon it,…
Astronomy · Celestial globes
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
