Dr. Barrow to Mr. Willughby. 3^ 



Let M N, OP, be 

 perpendicular to the 

 Horizon, and OZ, 

 MR, touch the Cir- 

 cle. 'Tis evident that 

 the Angle POQ = 

 Ang. NM R. Now 

 if the Point O de- 

 fcend, it mull: recede 

 from the Perpendi- 

 cular OP by the An- 

 gle POZ5 but if 

 M defcend, it re- 

 cedes frpm M N by 

 the Angle N MB, 

 which is lefs than the Angle POZ by z Ang. QOZ, 

 or z BMR. Therefore Mwill more eafily defcend 

 than O, and hath the more advantagious Situation 

 for the Exercife of its natural Propenfion, Like- 

 wife if M afcend, it muft recede farther from the Per- 

 pendicular M K, &c. 



You may alfo confider whether O ftriving to 

 move, and not being able both to overcome the 

 Refinance of M to afcend, and its endeavour to 

 defcend, doth therefore (being in Motion) fomewhat 

 recoil, and fo continues till both come into a Hori- 

 zontal Pofition. 



I have no more concerning thefe things, but yet 

 I am ever, &c. 



I might add, that if the > Jf£ 



Prop, have any Latitude, 

 it falls to the Advantage 

 of the upper Weight c 

 for the Line MO will reft 

 upon the Point Q, and q 

 MQJs greater than OQ, 

 whence the Weight M will exceed, &c. I fuppofe 

 the more exa&ly the Scales are made, the lefs the 

 Effeft will appear. Bijhop 



