→ See the front page for how to read the Notebooks by RSS.
Page 891 of 1565.
Previous / Next
A METHOD OF SEEING THE SUN ECLIPSED WITHOUT PAIN TO THE EYE.
Take a piece of paper and pierce holes in it with a needle, and look
at the sun through these holes.
III.
THE MOON.
On the luminousity of the moon (892-901).