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. As to the general question 



and other less maritime countries. As to the general question 

 of the migration of birds, it has been argued that the lines of 

 flight followed by birds in migration, especially when crossing 

 seas, are the same lines that were taken by the remote ancestors 

 of these same birds ages ago, when it is believed much land 

 was above water which is now submerged. It has been further 

 argued that the habit of taking particular lines of flight has con- 

 tinued for thousands of years, and still exists, notwithstanding 

 the altered physical and geographical conditions. Plausible 

 and even attractive as that theory is, the essayist could not 

 coincide with it. The theory that the flight of birds in mi- 

 gration ordinarily takes place at high elevations is supported 

 by the fact that it is only in dark or cloudy weather that 

 migration on a large scale is observable. It has been noticed 

 that a stream of migration seemed suddenly to stop when the 

 moon rose. From its geographical position, Ireland is out of 

 the tract of migration. The uncertainty still attaching to some 

 of the migratory movements of birds invests them with an 

 interest, indeed we may say a charm, peculiarly their own, and 

 the study is one which, while it tends to the development 

 of both the observant and the reflective faculities, elevates the 

 mind, and leads us to regard with renewed admiration the 

 mysterious ways of nature. 



