Diagram, A new way for sounding the depth of the sea without a line by Robert Hooke Diagram illustrating Robert Hooke's invention for sounding the sea without a long line, using instead a ball sunk to the bottom of the sea by a weight which is released as soon as it touches the sea-floor and returns to the surface. Text next to diagram reads: 'Between the long wire-staple B of the Ball A I press in with my fingers a springing wire C, on the bended end F of which, I hang the weight D, by its ring E, and so let them down into the water in this posture, towards the bottom of which they are carried with a considerable swiftnes, which the weight D touching first, is thereby stopt, but the Ball, by the impetus, it acquired in descending, being carried downwards, a little after the other is stopt, suffers the springing wire C to fly back and thereby sets itself at liberty to reascend.' The design was discussed at the meeting of the Royal Society on 30 September 1663. Subject: Oceanography 30 September 1663