Paper, 'A device concerning a clock-hand' by Robert Hooke Description of an instrument for making accurate clock hands, and discussions of the sundial. Paper's full title: 'A description of an Instrument for making the hand or Index of an accurate Clock which moves equally swift at all times, to move unequally upon the plaine of any Dyall [dial] in the same proportions with the motion of the suns shadow upon that plaine. Or a Description of a very easy and simple Instrument but universall for the Description of all kinds of Plaine Dyalls, whether Horizontall murall inclined . . . Together with a Demonstration of the Principles and Reason of it.' Subject: Engineering 1667