PACE AND LAST 119 
contract 93,600 times! The red, stringy Depressor 
muscle can claim more credit for these marvellous 
flights than any of the others. The heart, the lungs, 
the whole machine, must be very strong and in 
perfect working order. 
Sometimes birds make long flights, requiring great 
endurance, in the course of their day-to-day life. 
Of this I give an astonishing example, which is 
vouched for by two highly competent observers : 
“Another fact that well-nigh struck dumb the 
authors was that Ducks shot at dawn at Daimiel are 
found to be crop-full of rice. Now the nearest rice 
grounds are at Valencia, distant 180 miles; hence 
these Ducks, not as a migratory effort, but merely 
as incidental to each night’s food supply, have sped 
at least 360 miles between dusk and dawn ’’*—and, 
we may add, are probably ready to do it again the 
next day and the next. Such a trifle as 360 miles 
seems to put no strain on the digestive apparatus 
or any part of the organism. The heaviest meal is 
dealt with easily and causes no torpidity. 
Whatever help the wind may give, it would seem 
to be a fair inference from the examples which I 
have quoted that birds surpass other animals in 
vitality. It is not for nothing that their normal 
temperature ranges in the case of some species to 
111° F., and even slightly over. 
* Unexplored Spain, p. 187, by Abel Chapman and Walter Buck: 
