ANIMAL MECHANICS. 315 



From these values, we find 



Q 2 - 4 PiZ = - 16.134, 

 showing that the equilibrium is always stable ; and 



The actual distance of the socket from the axis OF is ^fnds 

 of an inch. 



(e.) Wing of the Pheasant.— -The following measurements 

 were made on the wing of the Pheasant, in 32nds of an inch : — 



Angle. 



l-V. 



I sin 9. 



I sin 9'. 



o° 



13 



+ 22 



+ 16 



5 



40 



4 22 



+ 9 



JO 



66 



+ 20 



+ 5 



J 5 



74 



+ «4 



4 3 



20 



100 



+ 6 



+ 1 



2 5 



1 20 



- 5 



— 1 



30 



163 



- 23 



— 2 



35 



183 



- 42 



— 2 



40 



199 



-63 



- 3 



45 



216 



-85 



- 4 



From these measurements the following Table is con- 

 structed : — 



Wing of Pheasant. 





1 



(l+l') sin 9 



IV sin2 9 







Angle. 





l-V 



l-V 



o° 



0. 07692 



+ 2.9 2 3 r 



27.07 



5 



0.02500 



+ 0.7750 



4 95 



10 



0.01515 



+ 0.3788 



1-5' 



15 



0.01351 



-f 0. 2300 



o.57 



20 



0 01000 



+ 0.0700 



0 06 



25 



0.00833 



- 0.0500 



0.04 



3° 



0 .006 14 



~ 0. 1533 



0. 28 



35 



0.00547 



- 0. 2404 



o.49 



40 



0.00503 



" 0.3316 



o.95 



45 



0. 00463 



- 0. 4120 



1-59 



Sum, 0.17018 



3.1896 



37.51 



