270 Rotary Action of the Providence Tornado. 



shown. The figure was drawn from my field notes on account of the distinct 

 phenomena which were exhibited on this part of the track, and which, in cases a, 

 14, 22, 21, 23, and 27, show conclusively the first action of the whirl across the 

 path of the axis, and sweeping towards the northern border of the track. , On the 

 opposite or right side of the axis, southward of 15, there were no trees exposed, 

 and the eff"ects of the tornado were here visible only on the crops and fences. 

 Therefore the cases shown on the figure south of the axis, and also westward of 

 22 on the left side, were brought in from the more western parts of the track be- 

 tween the orchard and the river, and include all the prostrations from the latter to 

 Tifts' house ; and their relative distances from the axis or center of the track are 

 but approximated. 



Case 14, represents a small locust tree broken off" at an old wound near the root 

 and carried outward and backward into the adjoining fallow field, having struck 

 into the ground seven times in its course, leaving distinct traces. It was finally 

 left at a point N. 57° W. from its slump, at the distance of forty yards, with its 

 top turned southwardly, in conformity with its two last traces in the soft ground. 



Case 10, a small locust tree was prostrated S. 25° W., leaving its mark in the 

 fallow ground. It was subsequently shifted, by the progressive change in the 

 whirlwind, to S. 11° E. 



Case a, an old apple tree with but a single branch projecting southwardly from 

 its trunk ; this branch was taken off" by the onset of the tornado and struck into 

 the ground northwest from the trunk, depositing its apples at this spot. The limb 

 itself was missing. — Case 21, apples deposited as in case a. 



Case 22, a small wild cherry tree, was found lying on and against the stump of 

 14, having first been thrown from the latter by the onset of the wind and subse- 

 _ quently swung round by the south to its present position, as appeared by the im- 

 pressions made in the ground. Its final position was such, as if occurring at the 

 outset would have prevented 14 from being carried off northwesterly. — Case 23, 

 the branch of an apple tree was thrown west. — Atb is shown the relative position 

 of Tifts' house. 



Case 27, shows the original position of a large pear tree, the stem of which was 

 broken off" and first thrown northward, where it ploughed up the soft ground of 

 the garden by its force, and continued its circuit to a point northwest of its ori- 

 ginal position, where it remained with its top turned toward the south. 



For the purposes of a general comparison, the observed or first 

 known directions of the prostrations on the two sides of the track 

 may be summed up as follows. 



