166 ROYAL ASTRONOMICAL SOCIETY [1860-70 twelve months, shows how shortsighted such an anticipation would have been ; what an unexpected flood of light may some- times be thrown over one science by its union with another. Then follow references to the work of Bradley, Huggins, and Miller. The determination of radial proper motion in this way is still in its infancy. It is worthy of note that, unlike the detection of transversal proper motion by change of angular position, it is equally applicable to stars at all distances, provided they are bright enough to render the observations possible. It is conceivable that the results of these observations may one day lead to a determination of the motion of the solar system in space which is more trustworthy than that which has been deduced from changes of position, as being founded on a broader induction and not con- fined to conclusions derived from the stars in our neighbourhood. Herewith we close this chapter, feeling assured that with all its inadequacy it can hardly have failed to show that the Society was handing on a heritage calling for great endeavour.
