1. An experimental inquiry into the properties of carbonic acid gas or fixed air: its mode of operation, use in diseases, and most effectual method of relieving animals affected by it ; being an inaugural thesis, submitted to the examination of the Rev. John Ewing, S.T.P. provost ; the Trustees and medical faculty of the University of Pennsylvania, on the 12th day of May, 1797 ; for the degree of Doctor of Medicine Author(s): Johnson, Joseph, 1776-1862 Publication: Philadelphia : Printed for the author, by Stephen C. Ustick, 1797 Subject(s): Carbon Dioxide