The province of the armillary sphere was to make these measurements extremely accurate.
"A History of Science, Volume 1(of 5)" by Henry Smith Williams
At the top, the drip-mould grows into a large trefoil with crockets outside and an armillary sphere within.
"Portuguese Architecture" by Walter Crum Watson
When several rings or circles were combined representing the great circles of the heavens, the instrument became an armillary sphere.
"Encyclopaedia Britannica, 11th Edition, Volume 2, Slice 5" by Various
An armillary sphere, in bronze, supported by three lions.
"Annals of the Bodleian Library, Oxford, A.D. 1598-A.D. 1867" by William Dunn Macray
The astrolabe, of course, but also the nocturnal, armillary spheres, cross staff, quadrant, dioptra, and (on p. 193) that funny-looking star-burst on a stick that old astronomers (we mean 15th century or something, not ourselves) are sometimes shown holding.
Astrophysics in 2006