The Variation of the Compass; Containing 1719 Observations to, in, and from, the East Indies, Guinea, West Indies, and Mediterranean, with the Latitudes and Longitudes at the Time of Observation. The Longitude for the Most Part Reckoned from the Meridian of London; If Otherwise, It is Taken Notice of in the Margin. By Mr. Robert Douglass. Recommended to the Public by the Late Dr. Halley. Communicated by the Rev. Nevil Maskelyne, Astronomer Royal, F. R. S. with a Letter Prefixed from William Mountaine, Esq. F. R. S. to Mr. Maskelyne
R. Douglass, W. Mountaine, N. Maskelyne, E. Halley