922 Col. R. Meineitzhageu on the Altitudt [Ibis, 



were thought to have been between 11)00 and 10,200 feet, one 

 between 2000 and 11,000 feet, and one between 2600 and 

 13,500 feet. 



In 1905, Carpenter (Auk, I'JOG, pp. 210-217) conducted 

 some experiments by night in May and October, with a 

 view to observing birds passing the face of the moon. In 

 May no bird was observed flying at over 2400 feet, the lowest 

 flying at 1200 feet. In October birds ranged from 1400 to 

 5400 feet. 



Lucanns, who appears to be much interested in this subject, 

 finds (J. f. 0. 1902, pp. 1-9) that migrants generally travel 

 at under 3300 feet above the earth and always below the 

 lowest clouds. A xery high altitude is unnecessary i'or 

 birds, because, according to aerial observations, the })er- 

 spective disappears at over about 3300 feet. Again (J. f. 0. 

 1913, pp. 117-124) he finds from observations made from 

 German air-ships, that the flight of birds is very seldom at 

 altitutles of over 1200 feet, whilst no birds have hitherto been 

 detected at an elevation exceeding 3000 feet. 



The following is an important scrap of evidence from India. 

 Donald (Journal Bombay Nat. Hist. Soc. xxv. 1917, p. 302), 

 when in the Himalaya at 14,000 feet above sea-level, observed 

 " Storks and Cranes'' flying in a north-easterly direction at 

 the end of May. They were not visible to the naked eye, 

 and could only with difliculty be seen through glasses. 

 Now I have" seen Geese at an altitude of over 4000 feet. 

 They were difficult to pick up, but once seen were easily 

 followed with the naked eye. If Donald's Cranes were 

 invisible to the naked eye, they must have been at least 

 6000 feet above ground level. 



Evidence from British Lighthouses is all too meagre. At 

 theTuscar Rock, Patten (' Zoologist,' 1013, p. 182) estimated 

 Pipits to fly at 70 feet above the sea. Swallows between -fO 

 and 100 feet, and Wagtails at about 120 feet. At the Eddy- 

 stone, Eagle-Clarke (Ibis, 1902, pp. 246-269) estimated 

 Meadow-Pipits to fly at about 20 leet above the sea, and 

 Wagtails between 130 and 200 feet. 



Ingram (Ibis, 1919, pp. 321-325) gives the following 



