If you will look closely at the back ones, you will see that each of them has four corners, or cusps, with a cross-shaped, sunken furrow in the centre, where they come together.
"A Handbook of Health"
Woods Hutchinson
One of the photograms of the partial eclipse that we took before totality, shews the cusps and edge of the moon to be double, giving the appearance of a band surrounding the moon.
"Canadian Eclipse Party 1869"
Commander E. D. Ashe
The windows in the south wall have lost their cusps, but they are retained in those in the north wall-and the library has in all points suffered less from modern interference than almost any other with which I am acquainted.
"The Care of Books"
John Willis Clark