From The Seaman's Secrets by John Davis (1594)

The Solstical Colure is a great circle paseing by the Poles of the world, and the Poles of the Zodiac, and the Solstical points or first minute of Capricorn and Cancer, cutting the Equinoctical at right spheric angles, in his 90 and his 270 degrees.

The Equinoctial Colure is likewise a great Circle passing by the Poles of the world, and the Equinoctial point of Aries and Libra, and crosseth the Equator in his 1 and 18 degrees.

These colours do intersect each other in the poles of the world to the right Spherick angles.

What is the use of these Colures? Their use is to distinguish the four principal seasons of the year,
Spring, Summer, Autumme, and Winter, dividing the Equator and Ecliptick into 4 equal parte: also that Arc of the Solstical Colure, which is included between the first minute of Cancer, & the Equinoctial, is the Sun's greatest declination toward the north, the like arc being between the tropical point of Capricorn and the Equator, is the Suns greatest south declination, being in (1657) 23 deg. 28 min.