Newton's revival of the aether hypothesis and the explanation of gravitational attraction

In his recent paper, ‘Newton’s Optical Aether’ (i), Professor Guerlac has uncovered much of interest in explanation of the format of the second English edition of the Opticks . That Newton intended that there should be a ‘Part II’ to the third book of the Opticks , seems now to be irrevocably proved, as also is the fact that the contents of this part were to include some of the electrostatic experiments of Hauksbee. It has previously been Professor Guerlac’s contention that these experiments of Hauksbee’s formed a distinct part in a revival of Newton’s belief in an aetherial medium (2), and in this recent paper he further suggests that for more, ‘persuasive experimental confirmation’ of the aether hypothesis, Newton devised the ‘two-thermometer experiment’ (3). I should like to suggest, and later in this paper to expound, that Newton’s interest in Hauksbee’s experiments, which were mostly performed between the years 1705-1712 (4), was related to a general interest in electrical phenomena and a specific interest in the attractive and repulsive forces exerted between the smallest particles of matter. Initially, however, there are other points which deserve of further consideration.