The Eyeballs and Their Muscles
The eyeballs and their muscles as seen when the roof of the orbit has been moved and the fat in the cavity has been partly cleared away. On the right side the superior rectus muscle has been cut away. Labels: a, external rectus; s, superior rectus; i, internal rectus; t, superior oblique.
Martin, H. Newell & Martin, Ernest G. The Human Body: An Account of Its Structure and Activities and the Conditions of its Healthy Working (New York: Henry Holt and Company, 1917) 247