An inaugural dissertation on the causes and effects of sleep : Submitted to the examination of the Rev. John Ewing, S.T.P. provost, the trustees and medical professors of the University of Pennsylvania, on the seventeenth day of May, 1796, for the degree of Doctor of Medicine. By Thomas Ball, of Virginia, member of the Philadelphia Medical Society. [One line from Young]. - Ball, Thomas. (Printed by Budd and Bartram, no. 58, North Second Street, 1796)