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ANIMAL MECHANICS. 



From these results we can calculate the equivalent fibre 

 00', as follows : — 



L L ' 



~p = - 0.009, p = + °-7 62 > 



P 2 = Z 2 + Z /2 + 4c 2 , 



P> = !1^ 9 F =6 .6 4in ., 



0.419 



L = - 0.06 in. 2/ = + 5.06 in. 



Laying down the points 0 and 0' on the bones, I found — 



Distance from 0 to centre of socket =5.16 in. 

 Distance from 0' to centre of socket = 6.40 „ 



Difference, . . . 1.24 in. 



These measurements correspond to an angle of $i° *}' 

 made by the fibre 00' with the plane passing through the 

 bone AB, or by equation (108). 



Work done . , nx 



m — = r = sin (20) = 97.7 per cent. 



Maximum work 1 



2. Adductor secundus (a). — This muscle takes its origin 

 along a surface 2.68 inches long, from the tuber ischii to the 

 posterior end of the symphysis pubis, and is inserted in continua- 

 tion of the insertion of adductor primus, higher up on the linea 

 aspera, for a length of 3.45 inches. It is more skew than 

 adductor primus, but less so than adductor secundus ((3). The 

 following measurements were made upon this muscle : — 



Lion — Adductor secundus (a). 



Lengths of equidistant Lengths of Origin and 

 Fibres. Insertion. 

 p = 5.34 in. a = 2.68 in. 



Pi = 6.40 „ a' = 3.45 „ 



2h = 7- 6 ° » 



