THE TEXAN MONSOONS. 
301 
On the January map their territory is not appreciably larger, 
while on the February map it is somewhat smaller. On 
the March map these winds do not appear at all. 
From an examinination of the weather maps it appears 
that occasional north winds, lasting several days, may occur 
in all months except the summer ones. They are occasional 
during the spring and autumn, and prevalent, and often long- 
continued, during the winter. 
They occur, for the most part, with anti-cyclones in lati¬ 
tudes north of Texas and east of the meridian of 110°. The 
control of the Texas winds by these centers in winter con¬ 
tinues as the latter travel eastward until the latter approach 
or even reach the Atlantic coast. Whatever the position of 
the center of high pressure, within the limits above given, 
its effect in Texas, and sometimes far northward, is to give 
generally north winds. 
There are also north winds of cyclonic origin, covering 
much more territory in the rear of cyclones in winter than 
in summer. An illustration can be found on the weather 
map for December 25th, a. m., 1890. In the case of the rare 
cyclones with a cold center, which is apparently an ordinary 
cyclone turned upside down, it is, of course, the advancing 
or eastern side which promotes the occurrence of north winds 
over the plains and in Texas. Such a case may be found on 
the morning weather map for February 25,1891. 
The winter north winds differ from the summer south 
ones in several respects other than those of direction and 
season. They are less persistent under adverse circum¬ 
stances. They show less determination to push their way 
and are more easily suppressed, even in the midst of their 
proper season. They are most easily displaced on the coast, 
while the south winds are most persistent there. Indeed, 
they sometimes exist in the interior, while they are not pres¬ 
ent on the coast. For an illustration, see the weather maps 
for the morning and evening of November 28, 1891. 
The north winds are usually clear or clearing. Their 
velocity is generally higher than that of the summer south 
39—Bull. Phil. Soc., Wash., Vol. 12. 
