HISTORY OF ASTRONOMY.

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proceeding. Thofe two events feem to ftand at adistance from each other; it endeavours to bringthem together, but they refufe to unite; and itfeels, or imagines it feels, something like a gapor interval betwixt them. It naturally hesitates,and, as it were, pauses upon the brink of thisinterval; it endeavours to find out somethingwhich may fill up the gap, which, like a bridge,may fo far at leaf! unite thofe seemingly distantobjeds, as to render the passage of the thoughtbetwixt them smooth, and natural, and easy.The supposition of a chain of intermediate, thoughinvisible, events, which succeed each other in atrain similar to that in which the imagination hasbeen accustomed to move, and which link toge-ther thofe two disjointed appearances, is the onlymeans by which the imagination can fill up thisinterval, is-the only bridge which, if one mayfay fo, can smooth its passage from the one objectto the other. Thus, when we observe the mo-tion of the iron, in confequence of that of theloadstone, we gaze and helitate, and feel a wantof connexion betwixt two events which followone another in fo unusual a train. But when,with Des Cartes , we imagine certain invisible ef-fluvia to circulate round one of them, and bytheir repeated impulfes to impel the other, bothto move towards it, and to follow its motion, wefill up the interval betwixt them, we join themtogether by a fort of bridge, and thus take off thathesitation and difficulty which the imaginationfelt in palling from the one to the other. That