"It had been long observed that the position of the fixed stars were subject to some variations, which in no sort corresponded with the apparent motion of a degree in seventy-two years, which gives the precission of the equinoxes. The late abbe Picard had remarked these variations in the pole star in 1671, but he did not attempt either to reduce them to any settled rule, or to account for them. Dr. Bradley not only verified Picard's observations, but discovered many other variations which had never before been thought of; he found that some stars appeared to have, in the space of about a year, a variation of longitude backward and forward, but without any variation of latitude, that others, varied in latitude, but not in longitude, and others, by far the greater number, appeared to describe, in the space of a year, a small ellipsis, of different degrees of elongation. The period of a year, in which all these motions, so different from each other, were performed, seemed to prove, that they had a connection with the revolution of the earth in its orbit; but the difficulty was to discover in what manner the stars were apparently influenced by that revolution; this was attempted for some time by Mr. Bradley, but without success; at last, however, his sagacity and his diligence surmounted all difficulties, and he found the cause of these seemingly capricious appearances in the successive motion of light co-operating with the motion of the earth round the sun."