ON the evening of July 24 I had the opportunity of measuring the speed of an eagle's flight with greater accuracy than is usually possible. From my house I was gazing at the several summits of An Teallach (3,483 ft. and three miles away) through a stalking telescope. I noticed an eagle in the air above Sail Liath (3,150 ft.). The eagle's flight was irregular and on more careful scrutiny it was possible to see two peregrine falcons stooping at her. The eagle soared to about 5,000 ft., coming nearer, and from an undetermined position made a downward sweep across the glen and out of sight on Meall an Duibha behind my house. The peregrines followed but were left behind. The time taken on this downward flight was about one minute and the distance approximately three miles.