THE JOURNEYINGS OF BIRDS. 327 



later, may be actually seen by powerful telescopes. Woods and hedge- 

 rows that were untenanted one day may become fairly alive with birds 

 at daylight the next morning, showing that they have arrived during 

 the night. They remain to feed and rest during the day, and, if the 

 weather be favorable, may practically all disappear the next night. 

 That they only venture on these journeys during clear nights is 

 shown by the fact that on such nights very few birds are killed by 

 lighthouses, monuments or other obstructions, whereas on cloudy or 

 rainy nights, especially such as opened clear and later become over- 

 cast, thousands of birds become confused and dash themselves against 

 these obstructions. Thus over 1,500 birds have been found dead at 

 the base of the Bartholdi statue in New York harbor in a single morn- 

 ing, and 230 birds of one species — black-poll warblers — were killed in 

 a single night (Sept. 30, 1883) by the Fire Island light. The Wash- 

 ington monument, although not illuminated at night, causes the death 

 of hundreds of birds annually. 



The height above the earth at which migrating birds travel has 

 been made the subject of some interesting observations, the first of 

 which appear to have been by Mr. W. E. D. Scott, on the night of 

 October 19, 1880, at Princeton, New Jersey. In company with a num- 

 ber of visitors he was being shown through the astronomical observ- 

 atory at that place, and after looking at a number of objects through 

 the 91/^-inch equatorial, they were shown the moon, then a few days 

 past its full phase. His attention was at once arrested by numbers of - 

 small birds that could be more or less plainly seen passing across the 

 field of observation. Most of the kinds seen were the smaller land 

 birds, among which were plainly recognized warblers, finches, wood- 

 peckers and black-birds. He was able to identify with much certainty 

 the characteristic undulating fiight of the goldfinch, and the broad 

 boat-shaped tail of the purple grackle. The flight of the birds noted 

 was apparently nearly at right angles to the field of observation, and 

 they were passing at the rate of 4% per minute. As nearly as could 

 be estimated their height above the earth was between one and two 

 miles. 



In the following year similar observations were made by Scott 

 and Dr. J. A. Allen, but the results were not as striking, only 13 

 birds passing in any quarter of an hour. They were also apparently 

 flying lower than on the first occasion. 



Some years later observations on nocturnal flight were taken up 

 by Mr. Chapman, who spent three hours on the night of September 3, 

 1887, at Tenafly, New Jersey. During this time 362 birds passed 

 across the moon's face. Of these 233 were computed to be at a height 

 of from 1,500 to 15,100 feet, and curiously the lowest birds seemed 

 to be flying upward, as though they 'had arisen in the immediate 



