sounding-balloon
A Dictionary of Aviation · 1911 · p. 23
‘saun-din-ba,oun n. 4. a balloon used for sounding or invest a gating the air or atmosfere, as a small secondary balloon used by aeronauts for detecting airzcurrents at some distance from the main balloon.: 2. a small unmand hydrogen-fild balloon, now usually made of thin rubber, carrying meteorolegrcal imstyuments and dispatcht to great altitudes where the gasbag usually explodes allowing the mnstruments to descend slowly by the aid of a parachute; a ballon sende.
Readham'da tam maddeyi gor →