iSSS.] 



Chapman on Nocturnal Migration of Birds 



39 



9.36 two Carolina Rails, at 9.30 a large Snipe, at 9.33 a Caro- 

 lina Rail, at 10.15 a Carolina Rail, and at 10.44 '^ Duck. 



The major portion, however, passed at what may be termed the 

 middle distance, or, in other words, too rapidly for us to more 

 than distinguish that they were birds. During the first lialf 

 hour of observation a number of birds were seen flying upward, 

 crossing the m )on, thei-efore, iliagonally, these evidently being 

 birds which had arisen in our immediate neighborhood, and 

 were seeking the proper elevation at which to continue their 

 flight, but after that time the line of flight was parallel to the 

 earth's surface, the general direction being south. 



In the appended table the figures given in the vertical columns 

 headed i, 2, 3, etc., are the numbers of birds observed per min- 

 ute, the time being found by adding to that of the left-hand col- 

 umn the desired number at the head of the column following ; 

 to the right appear the totals and altitudes. 



In conclusion I desire to express my thanks to Mr. Paulison 

 for so courteously permitting us to use his observatory, and 

 especially to my friend Mr. Tatlock, who, in preparing its astro- 

 nomical portion, deserves entire credit for whatever value this 

 paper may possess. 



Table showing Time and approximate Height at which the 

 Birds observed flew. 



Height, 



sup. 

 limit. 



FT.* 

 3,200 

 4,000 

 4,900 

 .5.700 

 6,500 



7>3oo 

 8,000 

 8,Soo 

 9,500 

 10,200 

 1,000 

 1,600 

 12,200 

 12,900 

 13.500 

 14,000 

 14,600 



l?.IOO 



*Calculated to nearest 100 feet. 



