I. A true copy of a paper found, in the hand writing of Sir Isaac Newton, among the papers of the late Dr. Halley, containing a description of an instrument for observing the Moon's distance from the fixt stars at sea.

In the annexed Scheme, <italic>P Q R S</italic> denotes a Plate of Brass, accurately divided in the Limb into <italic>DQ</italic>, into 1/2 Degrees, 1/2 Minutes, and 1/12 Minutes, by a Diagonal Scale; and the 1/2 Degrees, and 1/2 Mi­nutes, and 1/12 Minutes, counted for Degrees, Minutes, and 1/6 Minutes.