XLI. Introduction to the following observations, made by Messieurs Charles Mason and Jeremiah Dixon, for determining the length of a degree of latitude, in the provinces of Maryland and Pennsylvania, in North America; by the Reverend Nevil Maskelyne, B. D. F. R. S. Astronomer Royal

Abstract

Messieurs Charles Mason and Jeremiah Dixon, who observed the last transit of Venus over the sun, at the Cape of Good Hope, under the direction of the Royal Society, had been since engaged, by the Right Honourable Lord Baltimore and the Honourable Mr. Penn, to settle the limits between the provinces of Maryland and Pennsylvania, in North America; which they performed partly by trigonometrical, and partly by astronomical observations.