THE FLIGHT OF THE BIRD 143 
yards. When the steamer was halfway across, flocks 
of Murres, returning to Bogoslof after long quests for 
food, began to break through the fog wall astern, fly 
side by side with the vessels, and disappear in the mists 
ahead. By chart and compass, the ship was heading 
straight for the island; but its course was no more exact 
than that taken by the birds. The power which carried 
them unerringly home over the ocean wastes, whatever 
its nature, may be called ‘a sense of direction.’ We 
recognize in ourselves the possession of some such sense, 
though imperfect and easily at fault. Doubtless a 
similar, but vastly more acute, sense enabled the Murres, 
flying from home and circling wide over the water, to 
keep in mind the direction of their nests and return to 
them without the aid of sight. It is probable that this 
faculty is exercised during migration. 
‘Reports from lighthouses in southern Florida show 
that birds leave Cuba on cloudy nights when they cannot 
possibly see the Florida shores, and safely reach their 
destination, provided no change occurs in the weather. 
But if meantime the wind changes or a storm arises to 
throw them out of their reckoning, they become be- 
wildered, lose their way, and fly toward the lighthouse 
beacon. Unless killed by striking the lantern, they 
hover near or alight on the balcony, to continue their 
flight when morning breaks, or, the storm ceasing, a 
clear sky allows them once more to determine the proper 
course. 
‘“‘ Birds flying over the Gulf of Mexico to Louisiana, 
even if they ascended to the height of five miles, would 
still be unable to see a third of the way across. Never- 
