216 NATURAL HISTORY 
and hold under their tongue. In general they feed 
in a much higher district than the other species; 
a proof that gnats and other insects do also abound 
to a considerable height in the air; they also range 
to vast distances, since locomotion is no labour 
to them, who are endowed with such wonderful 
powers of wing. Their powers seem to be in pro- 
portion to their levers; and their wings are longer 
in proportion than those of almost any other bird. 
When they mute, or ease themselves in flight, they 
raise their wings, and make them meet over their 
backs. 
At some certain times in the summer I had 
remarked that swifts were hawking very low for 
hours together over pools and streams, and could 
not help inquiring into the object of their pursuit, 
that induced them to descend so much below their 
usual range. After some trouble, I found that they 
were taking phrygane, ephemera, libellule (cadew- 
flies, Mayflies, and dragon-flies), that were just 
emerged out of their aurelia state. I then no longer 
wondered that they should be so willing to stoop 
for a prey that afforded them such plentiful and 
succulent nourishment. 
They bring out their young about the middle or 
latter end of July ; but as these never become 
perchers, nor, that ever I could discern, are fed 
on the wing by their dams, the coming forth of the 
young is not so notorious as in the other species. 
On the 30th of last June I untiled the eaves of a 
house where many pairs build, and found in each 
nest only two squab, naked pul!i; on the 8th of 
July I repeated the same inquiry, and found they 
had made very little progress towards a fledged 
