156 SIDE THOUGHTS ABOUT BIRDS. 
increased. The work of each depends for its success upon 
that of the others, and derives its special value from such 
co-ordination. 
A great change has taken place since the observation and 
study of birds was confined to a comparatively few men, who 
worked with little other motive than a love for searching out 
the haunts and habits of their woodland, field, and roadside 
friends. Popular thought has been turned to the ways of birds 
and the interest awakened in them, Of late years our best 
periodicals have given us many bright and charming glimpses 
of the homes and employments of the small fowl which make 
their summer quarters with us, or stay resolutely through 
the period of cold and snow. We have visited our “ little 
brothers of the air,” have looked at “birds through an opera 
glass,” and have learned that the student of birds is by no 
means of necessity a hoarder of dried skins, or a careless 
slayer of his friends. 
Perhaps of the practical applications of accumulated 
knowledge regarding birds, the most recent is that which is 
now being made by our Department of Agriculture and the 
allied experiment stations of the several States, in an attempt 
to determine what species are beneficial and what are harm- 
ful to agriculture. 
Naturally enough, the farmer takes particular notice of the 
birds which have their homes near or occasionally visit him, 
only when some pronounced useful or deleterious agency is 
often enough repeated to excite remark. Moreover, it is 
principally the damage suffered that he can estimate, for the 
gain in the destruction of noxious insects, field mice, go- 
phers, etc., is indirect, unlike the harm, which is always patent. 
Thus many birds are associated in his mind with rifled corn- 
fields and missing poultry. His own eyes have seen the 
wary Crows decamp from newly planted fields at his coming ; 
he has seen his rice field darkened with swarming Black- 
birds, and has many a time run out, gun in hand, just too 
late to save his fattest pullet. 
