Tycho's 1582 Triangular Sextant

Triangular Sextant, about 1.6 meter in radius, built in 1582. As Tycho's sextants grew in size, they became fixed instruments, although Tycho's ingenious globe mount retained a lot of the versatility of use of smaller, conventional portable sextants.

Bibliography:

Thoren, V.E. 1973, Journal for the History of Astronomy, 4, 25.

Wesley, W.G. 1978, Journal for the History of Astronomy, 9, 42.

Tycho