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 1 9 |  equal, the one at rest must bend either at the knee or, if
 2 9 |      that which moves cannot bend it will either fall forward
 3 9 |  goes forward therefore must bend, and while bending one,
 4 10|  like other limbs be able to bend at the point of attachment.
 5 12|      and birds, both bipeds, bend their legs in opposite directions,
 6 12|      further that quadrupeds bend their in opposite directions,
 7 12|    to a man’s limbs. For men bend their arms backwards, their
 8 12|    in like manner also birds bend theirs. The reason is that
 9 12|      set forth, but his arms bend backwards reasonably enough.
10 12|  also viviparous necessarily bend their front legs forwards.
11 12|   body. The reason that they bend forward is the same as in
12 12|    quadrupeds as well as men bend these legs forward in the
13 12|     better for their legs to bend thus when they are suckling
14 13|     pairs. Fore and hind may bend either both backwards, as
15 13|       as in C where the fore bend forwards and the hind bend
16 13|   bend forwards and the hind bend backwards, or as in D, the
17 14|    is the way then the limbs bend, and for the reasons given.
18 15|                     15~Birds bend their legs in the same way
19 15| sprawls over the ground, and bend them obliquely. The reason
20 15|     view of this they cannot bend them otherwise than outwards.~