THE TEXAN MONSOONS. 
297 
larger. It now lies to the southeast of a line drawn from 
Fort Sill, in the southwestern part of Indian Territory, to 
the mouth of the Pecos. 
In May it extends to a meridian perhaps fifty miles west¬ 
ward, and swells northward until it reaches the Dakotas, 
Minnesota, and Wisconsin—in fine, it extends fairly to the 
Dominion boundary. From June to September it remains 
about the same. In October it is as in May, and in Novem¬ 
ber it disappears. 
It is most extensive from May to October, when it occu¬ 
pies a territory ten degrees of longitude (about 500 miles) 
wide and fifteen degrees of latitude (about 1,000 miles) long. 
The examination of the daily weather maps for the year 
1891 and for fractions of other years brings out several note¬ 
worthy features in the relation of these southerly winds to 
cyclones and anti-cyclones. This northward draft of air 
between the Rocky mountains and the Mississippi river is 
frequently disturbed and modified by these independent 
wind systems. Sometimes the reach of the southerly winds 
is increased thereby; sometimes it is decreased ; sometimes 
it is suppressed, especially in the earlier and later months. 
Very rarely, however, are they entirely suppressed during 
the summer months. The}^ are apt to persist through all 
weather along the coast, especially west of Galveston, and 
.they show an invincible determination to extend them¬ 
selves northward through every gap where they can force 
their way. They frequently overcome the winds in the 
southwest quadrant of a cyclone lying immediately north¬ 
east (when the cyclonic winds are from the north), and in 
more than one case they were found pouring through be¬ 
tween cyclone and anti-cyclone when the currents of both 
these systems were against them. For the first, see the 
weather maps for May 18th, 26th, p. m., and June 7th, 
p. m.; for the last, see June 20th, all in 1891. 
But the wind systems of the cyclone and anti-cyclone are 
not always unfavorable. Sometimes they act in the same 
direction as the monsoon, in which case they extend it 
northward until it may reach beyond our northern frontier. 
