8 
POPULAR HISTORY OF BIRDS. 
after eight o^clock in the evenings after being almost in- 
cessantly engaged for nearly seventeen hours. Mr. "Weir 
counted their various returns to the nest^ and found them 
to be 475. Up to four o^ clock, as a breakfast, they were 
fed twelve times ; between five and six, forty times, flying 
to and from a plantation more than one hundred and fifty 
yards from their nest ; between nine and ten o^ clock, they 
fed them forty-six times, and they continued at their work 
till the time specified, sometimes bringing in a single large 
caterpillar, and at other times two or three small ones. 
The number of destructive insects removed by birds when 
feeding their young must be astonishing, if they are in any 
degree as active as the two blue titmice so patiently observed 
by Mr. Weir on the fourth of July, 1837. Great as the 
number of returns to the nest seems to be, it certainly does 
not exceed that of the common window swallow. 
Birds are divided into various orders, families, and tribes, 
'the characters being chiefly derived from the beak and feet. 
