1^4 HINTS RELATIVE TO 



rate bifogna in oltre avvertive, che quando V angolo 

 QVR non e retto, una porzione di Aq agifce fecondo 

 RV, ed una porzione di Ar fecondo QV : e feparando 

 le azioni fara MV, la teniione del hlo QV, ed NV 

 quella di RV." 



In the firft place, I fhall demonftrate the truth of 

 the eftabli fhed method from principles that Frisi has 

 himfelf allowed ; and, fecondly, point out the abfur- 

 dity of his conclulions. 



1. Let Vn and Sr be parallel to AN; then becaufe 

 NVn is a right angle, and the force VA may be refolved 

 into VN and Vn, in thofe directions, therefore, if RV 

 and VP were to remain in the fame pofition, and the 

 force which now keeps the body fufpended by a£ting in 

 the direction VQ, was to act in the direction VN with a 

 force exprefTed by Vn. it is then granted that the equili- 

 brium w< uld Mill be maintained, and the tenfions would 

 be as Vr: and VN; and, therefore, as no force VS what- 

 ever, actingat V in the direction RV, ran have any effect. 

 in the direction Vn perpendk ular «.o RV, it ne.. .Manly 

 follows, that the force in any other direction VO. mull 

 be fuch as to be equivalent to Vn in the direction Vn; 

 but it is likewift grankd, that no other force but Vr in 

 the direBion VQ can be equivalent to Vn in the direc- 

 tion Vn; and as the force Vr is equivalent to Vn and 

 VS, and as VS, or i ts equal, qN, only gives an additional 

 tenfion to N V, the tenfion which the cord RV was fup- 

 poftd to have before, which whole tenfion is equal to 

 the re-action of the tack R ; therefore qV is the tenfion 

 of the cord RV, and Vr that of Qv. 



2. Let the points Q and R coincide, and RV, QV, 

 and VP, will then be perpendicular to the horizon; 

 and if VQ or VR be aflumtd to exprefs the weight P, 



then 



