THE VICTOKIAN NATURALIST. 139 



Perhaps it will be well, before we go any further, to briefly 

 review the special points of interest connected with this group of 

 birds, scientifically known as the Diomedeae. They are, then, 

 essentially pelagic in their habits, and are found principally in 

 the southern seas. Stray specimens have been seen as far north 

 as Norway, but this is only evidence of their wonderful powers of 

 flight. They are nocturnal as well as diurnal, and have been 

 known to follow ships for weeks together ; indeed, Gould is of 

 opinion that they must often perform the circuit of the globe. 

 The flight of the Albatross has always excited wonder and 

 admiration. With its enormous stretch of wing it has brought 

 the science of soaring to perfection — the fiercer the gale the more 

 motionless are its wings, and the more easily does it circle 

 around, gracefully topping the billows. Professor Hutton's 

 theory that in soaring flight the wings are inclined upwards in 

 the direction of flight, although often adversely criticised, is 

 nevertheless the most feasible so far advanced. Recent experi- 

 ments have shown that the negative pressure on top caused by 

 rarefaction of the atmosphere plays an important part in support- 

 ing the bird. It seems likely that this pressure combines with 

 the upward pressure underneath to balance the force of gravity, 

 leaving the momentum to be utilized to the best possible advan- 

 tage. It is worthy of note that the aeroplane flying machine — the 

 latest product of the inventive genius of Mr. Hiram Maxim, and 

 the only machine which has ever actually risen from the ground — 

 is constructed on a similar principle. Mr. Maxim's experiments 

 have shown clearly the great advantage of driving an aeroplane 

 on to new air, the inertia of which has not been disturbed, and 

 that at high speeds the lifting power is much greater than it was 

 thought to be. 



Until an Albatross has acquired the necessary momentum it is 

 quite helpless, so that it cannot rise from the land unless it goes 

 to the edge of a cliff, and, in descending, gains the necessary 

 impetus. It rises from the water by dint of much flapping of its 

 wings and running on the surface with its broad-webbed feet. 

 To alight it is necessary to destroy the momentum. This is 

 effected by inclining its whole body to the wind, and with legs 

 stretched out and head thrown back it then presents a most 

 ungainly appearance. 



The breeding habits of the Abatrosses are little known, for they 

 haunt only the most isolated rocks. On Tristan da Cunha, 

 Prince Edward Island, and the Auckland and Campbell Islands, 

 the Wandering, Culminated, and Sooty Albatrosses are known to 

 breed, but we were in hopes that another species would be found 

 on Albatross Island. Nor were we disappointed, for the species 

 proved to be the Shy Albatross (Diomedea cauta.) This is a 

 beautiful form, with a snow-white crown and delicate grey cheeks 

 and neck. The stretch of wings is about eight feet. 



