218 The Bird 
ated in the inner ear—which occupy the three planes of 
space,—exercises a most important function, that of equi- 
libration. They have been compared to the glass tube 
filled with water and a shifting bubble of air, by centring 
which a surveyor knows his instrument is perfectly level. 
If these canals be injured or cut, the bird loses all 
control of his actions; if a certain one of the three canals 
suffers, the bird moves its head rapidly sideways and 
spins around in a circle; if another of the trio is by an 
accident severed, the motion of the head is back and 
forth, and the bird is compelled to execute forward som- 
ersaults; when the third of these canals is cut the bird 
continually falls backward. In reptiles and mammals 
the same thing occurs, so the wisdom of Nature in pro- 
tecting these delicate organs by a sheath of hard bone 
is very apparent. 
The Sense of Taste and Touch 
“The hands of birds being hidden in the feathers 
which envelop the whole body,—their feet and their lips 
and usually much, if not all, of their tongue, being 
sheathed in horn,—these two faculties would appear to 
be enjoyed in but small degree.” 
The sense of taste is probably the least developed 
of all. The nerves which find their way through the 
pores of the bill and tongue are more properly those of 
touch than of taste, and this seems the more credible 
when we consider the food of many birds, which is swal- 
lowed entire, besides being so hard that nerves of taste 
would be useless. Parrots and ducks, with their fleshy 
