6 E. Loomis— Results from an examination of the 
this comparison in 1874 was 80; and I have divided them 
into four equal classes, the first division embracing those cases 
in which the progress of the storm in one ay was at least 855 
miles; the second, those cases in which the progress was from 
855 to 665 miles; the third, from 665 to 490; and the fourth 
embracing the cases in which the progress was less than 490 
miles in one day. In the following table, columns one and two 
show the results heretofore published, derived from the obser- 
vations of 1872 and ’73; columns three and four show the 
results derived from the observations of 1874, while columns 
five and six show the results derived from combining the 
observations of the three years. 
Obs. of 1872 and 73. | Obs. of 1874. 83 years obs. 
Velocity — of 
in Led area | Velocity. | Rain-area.| Velocity. | Rain-area. 
per how Ga mile es. 
38°8 590 42°F 740 40-1 640 
28°5 548 30-7 609 29°2 568 
21°6 503 23°% 611 22°3 539 
14°5 365 17-0 535 15°3 422 
Although the velocity of progress does not appear to be 
strictly proportioned to the eastward extent of the rain-area 
(for the observations are seldom sufficiently numerous to indi- 
cate precisely the extent of this area, and it is plain that there 
are other causes which contribute to influence the result), yet I 
bia it is well established that an unusual extension of the 
n-area is generally accompanied by a velocity of progress 
greater than the mean. The result of the three years’ observa- 
tions shows the avuade extent of the rain-area eastward from 
the center of the storm to be 542 miles. When the eastern 
extent of the rain-area is 100 miles greater than the mean, the 
Hes 4 velocity of the storm’s progress is increased 13-7 miles ; 
but when the eastern extent of the rain-area is 100 miles less 
than the mean, the hourly velocity of the storm’s progress is 
diminished 9°5 miles. 
I have also determined the influence of the rain-area upon 
the direction of the storm’s path, as shown by the observations 
of 1874, in the same manner as described in my former paper 
(this Jour., vol. viii, p. 5). The oo table shows: first, 
from the observations of 1874; and shied, the results derived 
from combining the. pbaeriatie of the three years. 
