HURRICANES IN THE BAY OF NORTH AMERICA. 185 
southward, this rare phenomenon being due to the disturb¬ 
ing action of the upper currents of another simultaneous 
storm.” 
It has been observed that one hurricane often succeeds 
another and follows it at only a few days’ interval and along 
an almost identical track. Probably in this case the relative 
position and normal motion of each happens to be such that 
the repellent action is manifested by accelerating the first 
and retarding the second. In addition to the interest that 
attaches to this question from the point of view of theory, 
there is thus a side of great practical importance, since occa¬ 
sion might arise when two tropic cyclones were known to be 
in existence near each other and it were desired to predict 
the course each would follow. This chart shows that a sec¬ 
ond and very severe cyclone was in existence about 800 
miles east from St. Thomas, September 3, 1889, the very day 
that the first of these two September hurricanes passed the 
island. Now it seems possible, indeed, probable, that the 
delay of the first hurricane off our coast between Hatteras 
and Block Island was due to the area of high pressure built 
up between the two (as they moved north), southward of 
Newfoundland. Thus, just as in the case of the Cuban hur¬ 
ricane a year previously, the two cyclones modified each 
other’s movements. It is so often the case that two storms 
of moderate energy unite to form one storm of considerable 
energy, especially in the temperate zone, that it seems par¬ 
ticularly important to put on record the fact that two hurri¬ 
canes repel each other. That this is not the case where 
cyclones of moderate or slight energy are concerned, even in 
the tropics, is evidenced by a recent communication from 
Maxwell Hall, Jamaica Government Meteorologist, who re¬ 
fers to the union west of that island of two small depressions 
that passed on either side of Jamaica September 15th. Here, 
then, is one distinction, at least, between the movements of 
cyclones of slight and great intensity, and it will serve to 
illustrate what was said relative to the importance of study¬ 
ing the movements of hurricanes from the tracks of hurri- 
