106 MIGRATION AND FLIGHT. 



ignorance, we have enough left in the actual facts 

 of migration, to call forth all our wonder, in con- 

 sidering the regularity, order, and discipline, with 

 which these unaccountable journeys are conducted, 

 and the unknown compass placed within the bosoms 

 of these airy travellers, enabling them to go, and 

 return from, points thousands of miles apart, with 

 as much certainty, as the sailor steers his ship across 

 the wide ocean by his skill in navigation, and that 

 mysterious needle ever pointing to the north. 

 Neither is this instinct confined to birds; it has 

 been observed in turtles, which cross the ocean 

 from the Bay of Honduras to the Cayman Isles, 

 near Jamaica, a distance of 450 miles, without the 

 aid of chart or compass, and with an accuracy supe- 

 rior to human skill; for it is affirmed, that vessels 

 which have lost their latitude in hazy weather, have 

 steered entirely by the noise of the turtles in swim- 

 ming. The object of their voyage, as in the case of 

 birds, is for the purpose of laying their eggs on a 

 spot peculiarly favourable. 



It is, indeed, this instinctive power and stimulus 

 which is the real point to excite our astonishment in 

 the migration of birds; for when we take into con- 

 sideration what has been said of their rapid flight, 

 which would enable an Eagle, in nine days, allowing 

 him sixteen or seventeen hours for repose, to go round 

 the world, there is nothing so very extraordinary 

 in the journey of a Swallow from the shores of 

 England to those of Sierra Leone in Africa; where 

 a person, who resided there for seven years, con- 

 stantly observed our three species, many of them 

 remaining all the year, but their numbers much 



