Elements of theoretical and descriptive astronomy, for the use of colleges and academies (1901)
White, Charles J · New York: J. Wiley & sons · leaf 64
ation. Theangle P will be the greatest value of the heliocentric parallax,taken when the bodys elongation from the sun is 90°, and iscalled the annual parallax. We shall then find, from the for-mulae of Art. 54, that the animal parallax has for its sine theratio of the distance of the earth from… … 57. The dip of the horizon is the angular depression of thevisible horizon below the celestial £. Dhorizon. In Fig. 22, let EG be aportion of the earths surface, and 0the earths centre. Let a radius ofthe earth, CA, be prolonged to somepoint, D, beyond the surface, and letan observer be supposed to…
Astronomy
Internet Archive · Public Domain Mark 1.0. Free to use for anything.
![An illustration from L'optique divisée en trois livres : ou, l'On démontre d'une maniere aisée tout ce qui regarde 1. la propagation & les proprietez de la lumiere. 2. La vision. 3. La figure & la disposition des verres qui servent à la perfefectionner [sic] (1682)](https://img.insideoutlibrary.com/img/200/ia-loptiquedivise00ango-172-16.webp)
