Many persons know the story of the swallow which had entangled its claw, by some means, in a piece of thread fastened to a spout on the wall of the Collége des Quatre Nations, at Paris. Its strength being exhausted, the bird hung at the end of the thread, which it kept raising in the endeavours to fly, uttering plaintive cries. All the swallows from between the Pont des Tuileries and Pont Neuf, and perhaps still further, gathered together, to the number of some hundreds, all uttering cries of pity and alarm. After some hesitation and a tumultuous conference, one of them seemed to have found a means of delivering their unfortunate companion, and no doubt communicated it to the others. They placed themselves in order, and each coming in turn, struck the thread with the beak, somewhat after the fashion of ’tilting at the ring.’ These thrusts, aimed at the same point, succeeded each other every moment, and greatly incommoded the poor captive; but in a short time the thread was severed, and the poor bird set at liberty! The flock remained till night, chattering all the time; but in a tone which had nothing of inquietude, and was expressive only of mutual congratulation.
– Ernest Menault, The Intelligence of Animals, 1869