On the Inventor of Clock Movement applied to Equatorials—Suum Quique

Abstract

IN a pamphlet by Col. Laussedat, “On the Horizontal Astronomical Telescope,” in which he claims for himself the invention of applying a heliostat to direct the light of any object into a fixed telescope, I find at p. 2 this statement in speaking of the equatorial: “The idea of so endowing a telescope with a moving power which annuls, or, to speak more exactly, compensates the motion of the earth, is due to a French watchmaker of the last century, named Passemont.”