§ 
£. Loomis—Barometric Gradient in great storms. 459 
pany feeble winds we obtain an average gradient which is con- 
siderably too large. 
Date. Station. Barometer. as 
1877, Sept. 3.3_.__|/St. Panl, Minn. ..__- 29°80 0°070 inch. 
2. 2./ St.Paul; Minne. “80 “097 
10.1 <noxville, Tenn. ..-- 89 065 
Br a MADRS sacs. « “90 075 
13.3 Duluth, Minn. .....- “70 09 
21.1 iW, Me Waa 90 062 
99.4 Duluth, Minn. .....- a 6 "080 
9.3220. \ Ft: Sully, Dak. 2. s2. “42 “092 
On the other hand we sometimes find stations where the 
wind is very high and the gradient is small. If we examine 
the 250 cases of winds amounting to 40 miles per hour reported 
in my 8th paper we find that in several of them the gradient 
was very small. This will be seen from the following list 
where column sixth shows the gradient to one degree ex- 
pressed in decimals of an inch. 
Pa 
Date, Station. Barom. hogs coe oy 
ee ge Saou. Direct’n. |Veloe’y. : 
1872, Oct. 1.1_.|Indianola, Tex. ..... 29°99 N 43 0°053 inch 
1873, Jan. 8.2__|Key West, Fla. ....- 30°03 N 40 059 
..|Punta Rassa, Fla....| 29°93 NW 41 “049 
Feb, 22.3_ .|Indianola, Tex. _....| 30°17 N 48 049 
Noy. 5,22. 'Galves see 30°05 N 40 052 
2.1_.|Galveston, Tex... ... 30°21 N 0 “052 
Dec. 9.1_.\Ke Be oc 30°18 NE 40 052 
12.3__|Indianola, Tex. -_-_- 30°22 N 40 052 
1874, Jan. 4.1__/Indianola, Tex. _.._- 30°12 N 48 063 
4.2..,Indianola, Tex. _....| 30°25 N 40 063 
Apr. 17.1__ Indianola, Tex. -...- | 30°05 N 40 063 
| 
It will be noticed that all these stations are on the coast of 
the Gulf of Mexico; that in each case the wind was northerly, 
and all (with perhaps one exception) occurred during the pre- 
valence of what is popularly known as a norther. Now when 
we combine these cases of small gradients with the cases of 
Steep gradients which usually attend a wind of forty miles per 
hour, the average value of the gradient is very much reduced. 
Thus we find that by combining in a common average the 
observations from all portions of the United States in the man- 
ner adopted in my second paper, we obtain an average gradient 
which is too great for the small velocities of the wind, and too 
small for the high velocities. For a velocity of the wind 
amounting to about twenty-two miles per hour, the gradients 
