INDUCTIVE EPOCH OF NEWTON. 165 



knew not how to go about it. Now is not this very 

 fine ? Mathematicians that find out, settle, and do 

 all the business, must content themselves with 

 being nothing but dry calculators and drudges; and 

 another that does nothing but pretend and grasp at 

 all things, must carry away all the inventions, as 

 well of those that were to follow him as of those 

 that went before." This was written, however, 

 under the influence of some degree of mistake; and 

 in a subsequent letter, Newton says, " Now I under- 

 stand he was in some respects misrepresented to 

 me, I wish I had spared the postscript to my last," 

 in which is the passage just quoted. We see, by 

 the melting away of rival claims, the undivided 

 honour which belongs to Newton, as the real dis- 

 coverer of the proposition now under notice. We 

 may add, that in the sequel of the third Section of 

 the Principia, he has traced its consequences, and 

 solved various problems flowing from it with his 

 usual fertility and beauty of mathematical resource; 

 and has there shown the necessary connexion of 

 Kepler's third law with his first and second. 



3. Moon's Gravity to the Earth. Though others 

 had considered cosmical forces as governed by the 

 general laws of motion, it does not appear that they 

 had identified such forces with the force of terres- 

 trial gravity. This step in Newton's discoveries has 

 generally been the most spoken of by superficial 

 thinkers; and a false kind of interest has been 

 attached to it, from the story of its being suggested 



