For over two years Tutor Johnson was the sole member of the Yale faculty and the only administrator on-site at the college in New Haven. Unsupervised, he took the opportunity to introduce the Enlightenment into Yale. When Johnson's close friend Daniel Brown left his position as Rector of Hopkin's Grammar School and was formally hired as a second tutor in 1718, Johnson found time to create the first catalog of books of Yale's expanded library, and, between 1717 and 1719, to write up "Historical Remarks Concerning the Collegiate School", the first history of Yale. Johnson's first publication was a broadside printed for the 1718 Yale Commencement, which contained Latin commencement thesis. It shows that Johnson taught Locke, Newton, Copernican astronomy, modern medicine and biology, and, for the first time in an American college, algebra.