Rt* 1 7 



Ic of levers of kind b found in tbe animal frame, 



construction of which it seems to be a prefeiUag prm- 



i I 



to AAcnncQ power to VBMUIMM HIM! QUICADCM jM 01100* 



usls are gem 



omly Ic of the bone rests in its socket as tbe fulcrum ; a 

 < muscle attached to the bone near tbe condylc ia tbe 

 , and the weight of tbe limb together witn any re- 

 >ce opposed to iu motion U the * 



muscle gives a considerable motion to tbe limb. 



i to determine tbe weight of 



mces. Under this character it U called a Balance. Tbe 

 uon Balance bas iu two arms wiual. with a scale em> 

 d from each extremity; the fulcrum being oAocv the 

 ; o of gravity of tbe beam and therefore above the 

 formed by tbe beam, the 



.... * 



the weigh scales. The substance to be weighed is 



placed in one scale, and weigliU placed in tbe otk- 



beam remains in c.}utlit>rium in A ; ricctly horiaoatal posi 



horisontality of the beam wUl be die- 

 and after oscilUting for some time, in oooseqomce of 



:ig placed abon the 

 11, on attaining a state 

 /.on, tbe extent of which 



balance, 

 n we take tbe weight in tbe other scale as a measure of 



." .1 _ ' . ,_ m aVH . ^r^tolfcl.t^ ^f^ i ^*t*^m^ fk t 



!ie lever are of equal length and that the beam 

 I scales were em i 



. . . . . 



. . 



of rest, form an angle 

 ch U a uieasMi of tbe 



lid be iuclf in equilibrium It the sosJes were empty. 



us are satisfied by observing 

 equilibri 



scale w ! \reigbt oripnalir o 



ich tbe substance ongiaaUj 

 i the construction of a balance tbe following re- 

 led to. 



>aded with equal freights the beam should be 

 ly horizontal. 



(S) veigbts differ, cren b/ *lWit sjmmti- 



should be sudi as to detect tbis di&mice, 



