THE TEXAN MONSOONS. 
BY 
Mark Walrod Harrington. 
[Read before the Society, January 6, 1894.] 
By seasonal winds is meant those which continue in the 
same direction for periods which are measured by months 
and recur in the same seasons. The ordinary charts giving 
the resultant, or average direction do not admit of safe con¬ 
clusions on such winds. On the contrary, the tendency is 
to eliminate them. For instance, if at any station the wind 
was generally north for one-half of the year and south for 
the other half, except as modified by cyclonic or anti-cyclonic 
action, the last would, though exceptional, give character to 
the charts, and the more interesting periodic wind might be 
completely eliminated. 
In order to ascertain the locality and character of annu¬ 
ally recurring winds of considerable duration, maps were 
constructed showing the most frequent winds for each 
month of the year. The tables employed were the manu¬ 
script ones of the Weather Bureau, which give the mean 
monthly frequency for the eight principal points of the 
compass for the tri-daily observations from 1871 to 1886, 
inclusive. The tri-daily observations were used because 
they would give less prominence to land and sea breezes 
than would the later bi-daily observations. On these charts 
were marked all winds occurring with a frequency of two- 
eighths of all the observations or more, and the same for 
three-eighths, four-eighths, and five-eighths. Of the latter 
there were only three cases. Alaska was, of course, omitted, 
as we have few data from that region. 
38 —Bull Phil. Soc., Wash., Vol. 12. 
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