OF NATURAL PHILOSOPHY. 273 



as necessary consequences from the same general 

 law of force ; and how the orbits of comets them- 

 selves are only particular cases of planetary move- 

 ments. Thence proceeding to applications of greater 

 difficulty, he explains how the perplexing inequa- 

 lities of the moon's motion result from the sun's 

 disturbing action ; how tides arise from the unequal 

 attraction of the sun as well as of the moon on the 

 earth, and the ocean which surrounds it; and, lastly, 

 how the precession of the equinoxes is a necessary 

 consequence of the very same law. 



(303.) The immediate successors of Newton found 

 full occupation in verifying his discoveries, and in 

 extending and improving the mathematical methods 

 which it had now become manifest were to prove the 

 keys to an inexhaustible treasure of knowledge. The 

 simultaneous but independent discovery of a me- 

 thod of mathematical investigation in every respect 

 similar to that of Newton, by Leibnitz, while it 

 created a degree of national jealousy which can now 

 only be regretted, had the effect of stimulating the 

 continental geometers to its cultivation, and im- 

 pressing on it a character more entirely independent 

 of the ancient geometry, to which Newton was 

 peculiarly attached. It was fortunate for science 

 that it did so ; for it was speedily found that (with 

 one fine exception on the part of our countryman 

 Maclaurin, followed up, after a long interval, by the 

 late Professor Robison of Edinburgh, with equal 

 elegance,) the geometry of Newton was like the 

 bow of Ulysses, which none but its master could 

 bend ; and that, to render his methods available 

 beyond the points to which he himself carried them, 



