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■drift to one side a little, having the appearance of flying left shoulder first, instead 

 of head first. With strong head winds retarding their passage, great numbers fall 

 into the sea and perish. 



With northerly and easterly winds, birds are observed often to fly high, and 

 with winds in opposite quarters, low, near the water. The state of the weather at 

 the time of passage, has, we think, more to do with the height at which they 

 travel, than direction of wind. Thus, in clear starlight nights, they travel high as a 

 rule; but in fog, rain, or snow, or in thick murky weather, low. In fogs or snow 

 they become oiuch puzzled ; and it is invariably under these adverse meteorological 

 conditions they are observed about light-houses and light-ships, or clamorously 

 careering above the lights of a town. The rays from the lanterns are not cast 

 upwards, but directed to the horizon, so that on a foggy night, to birds passing 

 some distance overhead, the light of a light-ship would appear as an illuminated 

 circle, a spot where the fog seems less dense, or a little brighter than the surroun- 

 ding gloom, more or less distinct, according to the height they are flying at. A flock 

 of migrating birds seeing this luminous haze below them, strike directly downwards, 

 coming out of the fog — as it has been described at the light-vessels — as if shot 

 through a funnel, and when they come within the rays of the reflectors, will dash 

 and circle round the lanterns for hours. 



Mr. Gätke is of opinion that the phenomena of the circling flock is probably pro- 

 duced by a continuous stream of birds constantly recruited from above, rather than 

 the same flock flying continuously around the light, and that as soon as birds find 

 out their mistake, they pass forward or rise above the fog to their former altitude. 



The destruction of birds on these occasions by dashing againts the lanterns, is somet- 

 imes very great; many hundreds often being gathered from the deck during the 

 night, killed or disabled, and probably a much larger proportion are lost overboard. 



The pace at which birds travel when migrating is a question on which it is 

 not easy to get reliable statistics. It is probable that woodcocks (Scolopax riisticula) 

 leaving the coast of Europe, at sundown, in October or November, would, with a 

 favourable passage, reach the western districts of Ireland before daybreak; and we 

 have drawn fairly reliable deductions from our schedules indicating that the flight 

 of a woodcock, when in full migratory swing, is equal to fifty-two miles an hour. 

 Migrants constantly over-shoot their mark, and get far out on the Atlantic before 

 daybi'eak ; when, finding their mistake, they will retui'n to the nearest land. 



In 1884, a remarkable migration of the rook (Corvus frugilegzts) wâs observed at 

 Tearaght and Skelligs — both stations several miles from the coast of Kerry. It lasted 

 for three weeks, from November 2nd to the 21st. The direction of fiight, from west 

 to east. The nearest land to the west being America, in which the rook is not found. 



One of the smallest of our European birds. Béguins cristatns, crosses the North 

 Sea, between the Elbe and the Humber, often in immense numbers, regularly in 

 October, the distance being 360 miles. Mr. Gätke is of opinion that the Swedish 

 blue-thi'oat (Cyanemla suecica) crosses Europe in a single fiight from the delta of the 

 Nile to Arctic Europe; and the American golden plover (Charadrius virgin icus) is 

 known to pass from Vancouver's Island to the Sandwich Islands — over 30° of latitude, 

 or 2,700 miles — in one continuous flight. 



A simultaneous passing of birds to and fro, of the same species, over the North 

 Sea in the vernal and autumnal migrations, both towards the E. and S. E., and to 

 the W. or N. W., is very clearly indicated in the reports. This phenomenon of a 

 cross-migration to and from the continent, proceeding at one and the same time, is 

 regularly recorded on the east coast of England, but is specially observable at those 

 light-ships stationed opposite to the south-east coast. 



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