Merlin

. . . and his “volumes of strange lore.”

Art: Hal Foster (from page 60, April 2, 1938).
Source: Prince Valiant (Vol. 1): 1937-1938 – Hal Foster (Fantagraphics Books, 2009).

See also the previous posts:
• Wise Merlin
• Seeking Merlin's Counsel
• An Appeal to Merlin
• Old Beyond Years
• “It Is Indeed I”