102 Birds of Lakeside and Prairie 



So the birds' friend took a hammer and drove a lot of wire 

 nails into the trunk of the tree, thus precluding the possibility 

 of climbing it. "I may lose the tree," said the nail-driver, 

 "but I hope to save the birds." He was hitting the last 

 blow with the hammer when the grosbeak came with a 

 straw in its mouth. It saw the man standing below, dropped 

 its building material, and fled. It never came back. It is 

 something more than a pity that the birds cannot at first sight 

 tell friend from foe. The robin sat on the nest all through 

 the nail-driving without as much as fluttering a feather. 



In the spring of 1899 I found the nest of a vesper sparrow 

 in a Highland Park field. The bird clung to its charge until 

 I almost stepped on it. Then it left the nest and gave an 

 acrobatic performance which, had its motive not been known, 

 would have been laughable. The bird was counterfeiting 

 injury and an inability to fly in the endeavor to draw the sup- 

 posed enemy from its treasure. This is a favorite trick of 

 many members of the sparrow tribe, and that it is at times 

 successful there isn't a doubt. The vesper sparrow that was 

 performing for my benefit spread one of its wings out and 

 dragged it along the ground as though it were broken. The 

 little creature propelled itself with its other wing, which it 

 beat violently against the grass blades. Finally, when it had 

 reached a point about ten yards from the nest, it spread both 

 wings to their fullest extent and skimmed the surface of the 

 green pasture as though it were using a pair of sculls. Eventu- 

 ally it flew away to join its mate, who was scolding vociferously 

 near at hand. So far from doing violence to the home of 

 that devoted mother, I performed a service for her by remov- 

 ing from the nest the egg which a cow-bird had deposited 

 there for the vesper sparrow to hatch. The hatching of this 



