Rotary ‘Action of the Providence Tornado. 271 
Left or North side of the Track. Right or South side of the Track. 
Inclination inw’rd and Inclination inw’rd and 
ger of ig ba “ d fr’m course Direction of _ sera: rf set — 
Case. prostratio rnado, Case. prostratio 
8 8. 11° E. 79 degr’s.| 37 N. 87° E. 3 pe s. 
4 S$. 10° E. 8 43 N. 30° E 60 
fell S. 25 W. turn- = 41 8. 85° EB; -5 
ad ; ed to Si . ; _— 42 East, 0 
11 4 : 64 
be 8. 55° E. 35 Mean direction of prostration on the 
13 8. 55° E. 35 right side of the track N, 73° E.: aver- 
14 ffes thrown N. Me: O47 age inclination inward from course of 
; W. (backward) tornado, seventeen degrees. 
15 E Mean direction of first prostrations on 
16 8. 30° E. 60 the left side of track, S. 4° W.: aver- 
17 8. 55° E, 35 age inclination inward and backward 
‘6 ae be from course of tornado, ninety four de- 
int ees. 
20 S; 27° E. 63 Relative inclinations of the two sides 
al N.55°W .(backw’rd) 215 to the line of axis, more than five to one, 
22 ; pee et 8 + 225 It is proper to mention, that the average 
: ies inward inclination of all the prostrations 
& Sa a ara - on the right side of the track for a dis- 
23 ; Yheotn aaa 183 tance of four miles east of the river was 
24 $.20°W. (backw'rd) 110 thirty degrees.* This however does not 
25 $.55° W. (backw’rd) 145 affect the conclusions in favor of rotation 
26 South, to the left 
27 first thrown N.10 W. 260 
These average results, on the two sides, together with the ob- 
servations already adduced, appear to me to afford decisive evi- 
dence of whirlwind rotation in this tornado, in the direction from 
right to left or which is contrary to the hands of a watch. In 
reference to this evidence and that exhibited in my paper on the 
New Brunswick tornado, I add from my prepared sketches the 
following figure, as an approximate illustration of the whirling 
action in these tornadoes, so far as this may be shown horizon- 
tally and by a stationary figure. 
Let the involuted lines or arrows on this figure be supposed to 
represent the motion of the wind at or near the bottom of a ver- 
tically cylindrical portion of the center of a tornado, comprising 
alength of radius equal to the greatest width of the prostrating 
power on the right of the axis of its path. Now if the tornado 
* This larger se gives a pee fous of inclination on the two sides of 
three to one. Near is found in two outside bands of prostra- 
tion, of equal with “(ables T and v,) shown in my survey —_ v Bruns- 
‘wick Tornado, See this Journal, Vol. x11, p. 78. 
