THE SKYLABK. 
roar of the traffic below. Within a few yards, on either side 
of the way of this main thoroughfare, are many pent-np courts 
and alleys, each teeming with houses of business and manufac- 
tories, where are employed thousands of women, and men, and 
girls, and boys, and for my part I consider they ought to be, 
I have no doubt they are, much obliged to the good shell-fish- 
monger for providing them with music, so superior to any- 
thing that can be got out of wind or string, that the heart 
instead of the feet is set dancing with gladness. 
Stbtjcttjbe oe the Skylabk. — Speaking of the skylark's 
wondrous structure, Mudie says, the accordance of the sky- 
lark’s song with the mode of ascent is worthy of notice. When 
the volutions of the spiral are narrow, and the bird changes its 
altitude rapidly in proportion to the whole quantity of flight, 
the song is partially suppressed, and it swells as the spiral 
widens, and sinks as it contracts ; so that though the notes may 
be the same, it is only when the lark sings, poised at the same 
height, that it sings in a uniform key. It gives a swelling song 
as it ascends, and a sinking one as it comes down, and even if 
it takes but one wheel in the air, as that wheel always includes 
an ascent or a descent, it varies the pitch of the song. 
“ The song of the lark, besides being a most accessible and 
delightful subject for common observation, is a very curious 
one for the physiologist. Everyone in the least conversant 
with the structure of birds must be aware that with them the 
organs of intonation and modulation are inward, deriving little 
assistance from the tongue, and none or next to none from the 
mandibles of the bill. The windpipe is the musical organ, and 
is often very curiously formed. Birds require that organ less 
for breathing than other animals having a windpipe and lungs, 
because of the air-cells and breathing tubes with which all 
parts of their bodies (and even their bones) are furnished. But 
these diffused breathing organs must act with least freedom 
when the bird is making the greatest efforts in motion — that 
is, when ascending or descending ; and in proportion as they 
cease to act, the trachea is the more required for the purpose 
of breathing. The skylark thus converts the atmosphere into 
a musical instrument of many stops, and so produces an ex- 
ceedingly wild and varied song, — a song which is, perhaps, not 
equal, either in power or compass in the single state, to that 
of many of the warblers, but one which is more varied in the 
whole ascension. All birds that sing ascending or descending 
have similar power, but none so perfect as the skylark.” 
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