PROGRESS IN TORNADO-PREDICTION. 313 



Maury, in an article entitled " Tornadoes and their Causes," attributes 

 the peculiar movement of our tornadoes to an upper air-current, which 

 at times has been seen to be " moving from the southwest at the rate 

 of one hundred miles an hour." In addition to this, Lieutenant Fin- 

 ley's descriptions of the thirteen tornadoes that occurred in Kansas, 

 May 29 and 30, 1879, give abundant evidence that the southwest air- 

 current forces the contest. Innumerable descriptions show that the 

 cloud in the northwest is heavy, black, and comparatively slow in its 

 movement, until struck by a light, rather smoky, and more rapidly 

 moving cloud from the southwest. Then the clouds rush to a com- 

 mon center, and there is a violent conflict of cuiTcnts, driving clouds 

 in every direction, up and down, round and round. Clouds like great 

 sheets of white smoke dash about in a frightful manner, with such 

 unnatural velocity that the observer is often panic-stricken, and flees 

 to the nearest cellar for safety. Finally a black, threatening mass 

 descends slowly toward the earth, whirling violently, but still mani- 

 festing confusion in form. This soon gives place to the peculiar 

 funnel-like shape, with definite outline so well known. It appears in- 

 tensely black, like coal-smoke issuing from a locomotive, and its trunk- 

 like form sometimes has a wrenching, spiral motion, like a snake hung 

 up by the head and writhing in agony. As white clouds approach 

 and are drawn into the vortex, the funnel-shaped trunk sways like an 

 elastic column. It sometimes rises, falls, and careens from side to 

 side like a balloon. Branches and trunks of trees, rails, tree-tops, 

 roofs, pieces of houses, straw, furniture, stoves, iron-work, lumber, 

 and other debris are seen flying about in the central part of the cloud, 

 but are gradually drawn upward and thrown out near the top, usually 

 not until the storm has progressed a mile or two farther on from a 

 given point. Dark masses of cloud are seen to shoot downward on 

 either side of the funnel, to enter it just above the ground, and to 

 apparently rush upward through the center and out at the top in a 

 terrific manner. Sometimes the funnel pauses and whirls with appar- 

 ently increased velocity, reducing everything to splinters, and leav- 

 ing scarcely a vestige of a house or clump of trees, all being ground 

 comparatively fine and carried away as chaff. At "Westwood, New 

 Jersey, October 4, 1885, fully three quarters of a school-house was 

 carried away from the foundation. Its fragments were scattered 

 along the storm's track for about half a mile, and the rest was seen 

 no more. The people at Westwood describe the roar of the tornado 

 as having a peculiar hollow, humming sound. It somewhat resembled 

 the rumbling of cars, or the booming of the sea. The sound is in- 

 describable and unlike any other in Nature. It is so loud that the 

 falling of heavy trees against the side of a house and the crash of 

 falling buildings are lost in the general roar. These facts attest the 

 tremendous rapidity of the air-currents. 



In addition to a downward movement of air, there is also a violent 



