46 MEMOIR OF CAMPER. 



versed the experiment, by introducing the instru- 

 ment into the windpipe, and discovered that the air 

 escaped through the small hole I had drilled. When 

 I drilled a hole in the bone of the thigh, the same 

 results did not follow. 



" It happened that the chest of the eagle had 

 been too much injured by the shot to allow me to 

 repeat all the experiments upon it. However, I di- 

 rected a stream of air through its thigh-bone, and 

 perceived that the lining membrane of the lungs, 

 which extended into the abdomen, formed a memp 

 branous conduit, which, running along with the ves- 

 sels of the leg, terminated at the foramen in the 

 thigh-bone, and thus offered a free passage by which 

 the air could enter. This redoubled my ardour to 

 push my researches farther." 



He then made experiments upon the turkey-cock, 

 and other domestic fowls, and also on the stork and 

 heath-cock. In the former, the structure was like 

 that of the owl : in the latter, again, it resembled 

 that of the eagle ; and, from this circumstance, he 

 inferred, that the transmission of air into the thigh- 

 bones was not common to all birds, but peculiar to 

 those which were strong on the wing. He also ex- 

 amined a great number of our most common birds, 

 such as the sparrow, the lark, &c. and thereby found 

 his views so far confirmed. 



In conclusion, he remarks (for we must not ex- 

 tend our analysis further), " I natter myself that I 

 have discovered, that, in many birds, and more cs- 



