Papers of John Guy Porter

A copy of Porter's script for 'The Night Sky in December' on Jupiter rising in the east, near Regulus in Leo, Venus becoming prominent in the evening sky, and Mars and Saturn rising in the east before dawn, with Mars near Zuben-Al-Genubi in Libra; constellation boundaries, the old star atlases and Eugene Delporte drawing up the boundaries of the constellations; and the alteration in the orientation of these boundaries due to precession, the fixed stars, nutation, aberration and parallax of stars, proper motion of the stars, and the different aspect of the constellations in the centuries to come.