The speed of carrier-pigeons appears to depend as much on
the clearness of their sight as .on the strength of their wings. In an experiment recently made with some Berlin pigeons, on a clear day, a. distance of over 300 miles, from Cologne to Berlin, was accomplished in five hours and a half, or at the rate of nearly sixty miles an hour ; while the most expeditious of a group let loose the next day—a day not of the same kind—took twelve hours to reach Berlin. Hence, it would appear that in the latter case a good deal of the pigeons' time waa taken up in exploring the country for landmarks, as was some of Mr. Forbes's, in his ride from Ulundi with the news of Lord Chelms- ford's victory. It is not instinct, but sight, by which the carrier- pigeon guides its flight.