The Thirsty Pigeon

A PIGEON, oppressed by excessive thirst, saw a goblet of water painted
on a signboard. Not supposing it to be only a picture, she flew towards
it with a loud whir and unwittingly dashed against the signboard,
jarring herself terribly. Having broken her wings by the blow, she fell
to the ground, and was caught by one of the bystanders.

Zeal should not outrun discretion.