from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A mounting for astronomical telescopes that permits both horizontal and vertical rotation.
- n. A telescope having such a mounting.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A telescope or surveying instrument that has a mount permitting both horizontal and vertical rotation
from the GNU version of the Collaborative International Dictionary of English
- n. An instrument for taking azimuths and altitudes simultaneously.
from The Century Dictionary and Cyclopedia
- n. An astronomical instrument for determining the altitudes and the azimuths of heavenly bodies.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. an instrument that measures the altitude and azimuth of celestial bodies; used in navigation
The instruments provided for the journey consisted of two barometers, two thermometers, two compasses, a sextant, two chronometers, an artificial horizon, and an altazimuth, to throw out the height of distant and inaccessible objects.
The instrument which they employ to measure the angles from which to deduce the height of the clouds is a peculiar form of altazimuth that was originally designed by Prof. Mohn, of Christiania, for measuring the parallax of the aurora borealis.
This is a remarkable result, and shows conclusively the superiority of the altazimuth to the photographic method of measuring the heights of clouds.
This figure shows the peculiar ocular part of the altazimuth, with the vertical and horizontal circles.
The camera and lens that I use habitually for photographing cloud forms -- not their angular height -- was planted a few feet from the altazimuth with which M. Ekholm was observing, and while he was measuring the necessary angles I took a picture of the clouds.
We saw that the altazimuth employed at Upsala had no lenses.
It resembles an astronomical altazimuth, but instead of a telescope it carries an open tube without any lenses.
Ransome and May, to construct an altazimuth with three-foot circles, and a five-foot telescope, in 1847.
Römer, star places, 10; invention of equatoreal and transit instrument, 120; of altazimuth, 121; velocity of light, 231; satellite transit on Jupiter, 291
He himself, however, by much more exact observations, with an excellent altazimuth, reduced the alleged error from 20 minutes to only 4-1/2, or to 9-40ths of its formerly supposed value.