Chap. 3. PHILOSOPHY. 217

again to recede as before ; but the inclination of the orbit inthe appulfe of the moon to each succeeding node is less thanat the preceding, till the nodes come again into the quar-ters. This will appear as follows. Let A (in fig. 104.) re-present one of the moon’s nodes placed between the pointof opposition B and the quarter C. Let the plane A D E palsthrough the earth T, and touch the path of the moon in A.Let the line A F G H be the path of the moon in her passagefrom A to H, where she crosses again the plane of the earth’smotion. This line will be convex toward the plane A D E, tillthe moon comes to G, where she is in the quarter ; and afterthis, between G and H, the fame line will be concave towardthis plane. All the time this line is convex toward the planeAVE, the nodes will recede; and on the contrary proceed,while it is concave to that plane. All this will easily be con-ceived from what has been before so largely explained. Butthe moon is longer in passing from A to G, than from G to H ;therefore the nodes recede a longer time, than they proceed ;consequently upon the whole, when the moon is arrived atH, the nodes will have receded, that is, the point H will fallbetween B and E. The inclination of the orbit will decrease,till the moon is arrived to the point F, in the middle betweenA and H. Through the passage between F and G the incli-nation will increase, but decrease again in the remaining partof the passage from G to H, and consequently at H must beless than at A. The like effects, both in respect to the nodesand inclination of the orbit, will take place in the followingpassage of the moon on the other side of the plane A BEG,from H, till it comes over that plane again in I.

Ff

42. Thus