The true time of keeping St. Matthias's-Day in leap-years : Shewing, that it is to be kept on the 24th, and not on the 25th of February, as some almanacks place it. Wherein are inserted, I. Dr. Wallis's letter to Bishop Fell, ... II. Arch-bishop Sancroft's order, ... III. Collections out of accounts of time. - Watts, Robert (printed for J. Downing, J. Knapton, J. Wyat, H. Clements, & J. Holland [and 4 others in London], 1712)