Q2 Correspondence. j^ 



On this coast, as far as I know, the adults of the Eskimo Curlew 

 (Numenius borealis) arrive first. I merely mention it, as this bird is very 

 closely allied to the Whimbrel {Numenius pkceopus) (see Gatke, page 

 460). This is also the case with the Hudsonian Curlew. 



Judging from the twenty-five years' shooting experience of one of my 

 friends at one of the larger fresh water ponds in Massachusetts, where the 

 shooting of Canada Geese {Brat/fa canadensis) has been made a specialty, 

 it appears that they migrate in broods. It makes little difference how 

 many birds may be travelling in company, for on alighting in the pond 

 (unless in very stormy weather) they separate, each gander and goose 

 with their young keeping together, the gander leading. 



My observations in relation to rate of speed and length of flight lead 

 me to believe that under very favorable conditions, such as flying before 

 a very strong wind, such birds as the American Golden Plover and 

 Eskimo Curlew for instance, will attain a speed of one hundred and fifty 

 to two hundred miles an hour. It is consequently not inconceivable to 

 me that under such favorable conditions they are able to reach the Argen- 

 tine Republic or Patagonia in one flight, or with a possible rest on the 

 ocean. Hence I cannot regard a flight, under favorable circumstances 

 across the Atlantic ocean, as any great hardship to many of our birds. — 

 George II. Mackay, Nantucket, Mass. 



CORRESPONDENCE. 



The Soaring of Birds and Currents of Air. 



To the Editors of ' The Auk ' : — 



Dear Sirs, — Allow me to call the attention of ornithologists to the 

 following question in which ornithology and meteorology join hands. 



In recent years, wind vanes have been devised to indicate the vertical 

 component of the wind's motion, and it has been shown that there is a 

 significant variation in the strength of this component in various kinds 

 of weather. .It has long been known that the diurnal variation of wind 

 velocity on land was due to local convectional ascending and descending 

 currents, these varying greatly at different times and places, according to 

 the nature of the land surface, the strength of sunshine, etc. 



In recent years, attention has frequently been called to the importance 

 of vertical currents in air movement as an aid in the flight of birds, 

 Professor Langley's studies being perhaps the most important in this 

 direction. 



