IOO 
Scott on the Migration of Birds . 
B 
Area of triangle B, A, C, = 0.07020 miles. 
Area of triangle b, A, c, = 0.00439 m il es * 
Therefore b, B, C, c == 0.06581 = 1-5.2 mile. 
Distance from A to B = four miles. 
Number of birds seen per minute — 4J. 
Number of birds per square mile per minute = 68. 
[Mr. Scott’s novel and important observations definitely esta'blish on a 
scientific basis several points in relation to the migration of birds that 
have heretofore rested almost wholly on conjecture and probability. 
We have, first, the fact that the nearest birds seen through the telescope 
must have been at least one mile §bove the earth, and may have ranged 
in elevation from one mile to fen* miles. It has been held that birds 
when migrating may fly at a sufficient height to be able to distinguish 
such prominent features of the landscape as coast lines, the principal 
water courses, and mountain chains over a wide area. Of this, thanks 
to Mr. Scott, we now have proof. It therefore follows that during clear 
nights birds are not without guidance during their long migratory jour- 
neys, while the state of bewilderment they exhibit during dark nights and 
thick weather becomes explainable on the ground of their inability to 
discern their usual landmarks, — points that have been assumed as probable 
but heretofore not actually proven. 
These observations further indicate that many of our smaller birds 
migrate not only at night but at a considerable elevation, — far beyond rec- 
ognition by ordinary means of observation. A promising field is here 
opened up, in which it is to be hoped investigation will be further pushed, 
not only by Mr. Scott but by others who may have opportunity therefor. — 
J. A. Allen.] 
