298 THE BIRDS OF THE BRITISH ISLES. 



least suspicion of danger it further submerges the body, and 

 after a dive will expose head and neck only until sure that the 

 coast is clear ; it often raises itself high in the water, flapping 

 its wings, and sometimes points the bill upward as if stretching. 

 Quick though it is on the surface or in the air, its best speed is 

 under water, when it can outstrip swiftly swimming fish, its 

 main food. Many good observers say that it uses its wings as 

 well as its feet when wishful to make a spurt, and though it has 

 been seen flying under water, I believe that the greatest speed 

 is attained when with wings held close to its sides it shoots 

 forward with strong lateral and simultaneous strokes. The 

 legs, set far back, move like those of a grebe, and are turned, 

 so as to "feather" and ofter little resistance, when brought 

 forward. The freedom with which the tarsi can be revolved 

 is shown by the habit of raising one foot above the back. 

 Saxby saw the wings of a Great Northern Diver used when it 

 towed a boat, swimming under water, but this is no evidence, 

 for the bird was wounded, and was tethered to the boat by one 

 foot ; it could not use the feet simultaneously. 



The dives are long, but their duration has at times been 

 exaggerated ; my own timing never exceeded fifty- three 

 seconds, and thirty was frequent ; two minutes has, however, 

 been recorded. If the bird is diving to a depth it takes a 

 header, first springing up in the water, but often it sinks with 

 hardly a swirl. Probably small fish are swallowed under 

 water, but I have seen a large flat fish brought to the surface, 

 and not swallowed until it had been shaken and bitten, its 

 bones well broken. After a dive it almost invariably sips 

 water, and often turns its head and wipes the side of its face 

 and probably the bill against its lower back. The call of the 

 divers is discordant and weird ; Seebohm likens it to the scream 

 of a tortured child ; it is a melancholy wail, an " uncouth 

 shriek." Miss Haviland, from whom I borrow the last 

 expression, also heard and saw the bird with uplifted bill utter 



