Actually, while strictly true that the "second" axis is parallel to the (celestial projection of) earth's equator, it does intersect it directly-so is more accurately called coincident with- parallel is not quite the best term. The secondary axis never changes latitude (declination). The telescope is attached to, and free to rotate about, that secondary axis, describing north-south motion- the ability to point at any declination. The equatorial motion is strictly a function of the polar, or primary axis. You can have an equatorial mount without any secondary axis at all. Declination can be changed by using a universal pivot joint- a ball and socket, for example. The mounts name is more accurately descriptive of the motion it imparts, rather than where one particular axis is pointing. Alt-Az as a descriptive name works for the same reason. And of course the English Yoke is also known as an equatorial, for the same reason. As is the equatorial fork. I was trying to be funny, I'll know better next time. The "where the second axis is pointing" definition is inadequate and not truly descriptive of, or universally applicative to, the kinematics of all equatorial mounts.

From: Canopus56 <canopus56@yahoo.com>

The equatorial mount takes its name from the fact that while the first drive-powered axis is parallel to the Earth's axis, the second is parallel to Earth's equator. The German Equatorial Mount (GEM) takes is name from the historical development that you note.

English Yoke mount is also known as the equatorial mount - for the same characteristic that its secondary axis is parallel to the Earth's equator.

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