“The double motion of a secondary planet is still more singular than that of its primary; for (taking the moon for an example) besides its particular revolution round the earth, which is performed in 27 days, 7 hours, 43 minutes, 4½ seconds; it is carried round the sun with the earth once a year. Of all the planetary motions, with which we have a tolerable acquaintance, that of the moon is the most intricate: upwards of twenty equations are necessary, in the great majority of cases, to reduce her mean to her true place; yet not one of them is derivable from the circumstance that she accompanies the earth in its revolution round the sun. They depend on the different distances of the earth from the sun in its annual revolution, the position of the lunar nodes, and various other causes, and not on the annual revolution itself, a motion which, of all others, might be expected to cause greater irregularities in her revolution round the earth than could be produced on that of the latter by the planetary attractions. Who can form an adequate conception of that influence of the earth which thus draws the moon with it round the sun, precisely in the same manner as if it were a part of the earth’s surface, notwithstanding the intervening distance of about 240,000 miles; and, at the same time, leaves undisturbed the moon’s proper motion round the earth? And what beneficent purposes are subserved by this harmony? In consequence of it, we have the periodical returns of new and full moon; and the ebbing and flowing of the sea, which depend on the various lunar phases, with respect to the sun and earth, (as if demonstrable from each of these phases being continually contemporaneous with the particular phenomenon of the tides,) always succeed each other with a regularity necessarily equal to that of the causes which produce them. Thus we see that God is continually present, supporting all things by his energy, and that, while his working is manifest, his ways are past finding out.” Thomson, in his descriptive, philosophical, moral, and religious poem, admirably well delineates the revolving seasons.