60 National Geographic Magazine. 
Paulsen’s discussion of the warm winter winds of Greenland is 
interesting. These unusual storm conditions last three or four 
days, or even longer, the temperature being at times from 35° 
to 40° Fahr. above the normal, and they appear principally with 
winds from northeast to southeast, which Hoffmeyer believes to 
be foehn winds. Paulsen contends that the extensive region 
over which these winds occur make the foehn theory untenable, 
and that a more reasonable explanation of these winds is to be 
found in the course of low areas passing along the coast or over 
Greenland. This appears evident from the fact that not the 
easterly winds only but the southerly winds share this high tem- 
perature, and that as low areas approach from the west, at first 
the regions of the Greenland coast within its influence have 
south to southwest winds. 
The question of wind pressures and wind velocities is a most 
important one in these days of great engineering problems, par- 
ticularly in connection with the stability of bridges and other 
large structures. 
_ Experimental determination of the constants of anemometric 
formule have recently been made both in England and this 
country. From results obtained in the English experiments it 
was concluded that the very widely used Robinson anemometer 
is not as satisfactory and reliable an instrument as a different 
form of anemometer devised by Mr. Dines. These conclusions, 
however, are not sustained by the American experiments, which 
were made by Professor C. F. Marvin, Signal Office, by means of a 
whirling apparatus, and under the most favorable circumstances, 
which yielded highly satisfactory results. Professor Marvin has 
lately made very careful open air comparisons of anemometers pre- 
viously tested on the whirling machine, which have shown that, 
owing in part to the irregular and gusty character of the wind 
movement in the open air, taken in connection with the effects 
arising from the moment of inertia of the cups, and the length 
of the arms of the anemometer, the constants determined by 
whirling machine methods need slight corrections and alterations 
to conform to the altered conditions of exposure of the instru- 
ments in the open air. This latter problem is now being experi- 
mentally studied at the Signal Office, and final results will soon 
be worked out. 
Professor Langley has also made very elaborate observations 
of pressures on plane and other surfaces inclined to the normal, 
