Of course, at noon a horizontal line across the sun's disc is parallel to the equator, but the position of that diameter of the sun which coincides with the ecliptic is not constant: at the summer and winter solstices this diameter coincides with the other, or is horizontal at noon; at the spring equinox the sun (which travels on the ecliptic) is passing towards the north of the equator, crossing that curve at an angle of 23-1/2 deg., so that the ecliptic coincides with that diameter of the sun which cuts the horizontal one at an angle of 23-1/2 deg.

and has its _left_ end above the horizontal diameter; and at the autumn equinox the sun is descending and the same description applies, only that the diameter (inclined 23-1/2 deg.

to the horizon) which has its _right_ end uppermost, now represents the ecliptic.

For intermediate dates, use the following little table:-- -- ------------------------------------------------------------------------ Date.

|Dec.