ANIMAL MKl'IIAMSM. 



They enable us, therefore, to trace iii fig. Ilia series of 

 liiu-s, each of which expresses, by its inclination with respect 



t<> tin- horizontal 

 ifil t<> tlif l 



tli.it \\liidi tli.' plain v of th wing 

 at this saint' portion of its course. 



