New Brunswick Tornado. 73 
five chains (110 yards) from the northern or left-hand margin of 
the track, lie in directions which are more or less backward from 
the course of the tornado. The prostrations in this part of the 
track are also for the most part less ge than on the opposite 
side of the axis,* a greater portion of the trees being left standi 
It sometimes happens, owing perhaps to the inward or uli 
motion having exceeded the progressive motion at a particular 
point, that some inclination backward will be found in the pros- 
trations on the progressive side of the whirl, as seen on the 
sketch, Nos. 77 to 80. But these unfrequent cases by no means 
compare with the numerous backward and sometimes outward 
prostrations, found on the reverse side of the whirl, as illustrated 
by Nos. 1, 3, 4, 7, 9, 10, 12, 13, &c. on the left side of the track. 
Thus we find here a satisfactory indication that this tornado was 
a whirlwind; and that the course of its rotation fe to the left 
in front. 
7. It is also apparent, that the prostrating po a whirl- 
wind on the side of its reverse motion as just considered, will be 
limited to a shorter distance than on the opposite or progressive 
side of its axis. 
This is seen in the more limited extent of the prostrations on 
the north or left margin of the track, as compared with the ex- 
tent of those which incline inward on the right side of the appa- 
rent axis. ‘There were many trees standing beyond the northern 
border of the track, but none had fallen. _ 
8. It follows, in like manner, that on that side of a whirlwind 
in which the rotary motion coincides with the progressive move- 
ment, the prostrating power will not only be increased in its in- 
tensity, but will also be effective over a wider space ; and that 
few, if any, of the prostrated bodies will be found to have been 
dato backward. 
In the case before us, as may be seen in the sketch, the pros- 
trations are found to cite on the southern or right side of the 
apparent axis to a distance nearly twice as great as on the left 
side. 'The same general result has also been noticed in the tracks 
of other tornadoes which I have examined. . 
* There was a vacant space in the belt of wood, immediately to the right of the 
line ¢ ¢ or axis of the tornado, owing to which the effect mentioned does not ap- 
pear so obvious in the figure ; 
Vol, xxi, No, 1.—April-June, 1841. 10 
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