> Also on the Sun3 Mouse there are two holes on the bottom and one has
> the red light in it.  What is the other hole used for?  If you open
> the mouse, both have lights hooked up to them, but only one hole
> radiates light.

Only one hole radiates *visible* light.  I imagine the other is
producing infrared or ultraviolet.  Based on selectively blocking the
lights, the red light is for horizontal motion and the other for
vertical motion.  If I had equipment to measure the absorption spectrum
of the ink used in the horizontal lines on the pad, I could offer a
guess as to which way the vertical light lies outside the visible.

Or, you could let a mouse sit on your arm for several hours and see if
you get a small spot suntan. :-)

					der Mouse

			       mouse@rodents.montreal.qc.ca
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