What is "aeroscopy"

Aeroscopy \A`["e]r*os"co*py\, n. [A["e]ro- + Gr. ? a looking out; ? to spy out.] The observation of the state and variations of the atmosphere.

n. 1 (context obsolete meteorology English) The branch of meteorology that involves the scientific examination of the various properties and composition of the atmosphere, and their variation 2 (context rare English) divination by observation of the sky 3 (context zoology English) aeroscepsy