10 " THE LEAVES OF THE TREE Were FOR THE HEALING OF THE NATIONS. 



due to a disturbance in the equilibrium of the atmosphere by the excessive rare- 

 fraction of the air at one particular spot with the sudden inrush from several direc- 

 tions to fill up the vacuity thus caused ; of these the sand-pillars of the Asiatic and 

 African deserts are the most striking concomitants, while at sea the water spouts 

 form the equivalent of the sand pillars which are the materialized bases ot the 

 "afreets" of the Oriental mythology upon the land. 



"The revolving of circular storms variously known as cyclones, tornadoes ^and 

 hurricanes are in some respect different from these. Indeed, though a cycione 

 and a tornado are in ordinary parlance considered synonymous terms, they are 

 metereologically distinguished by various points, special to each of them. _ Thus, 

 though a cyclone is generally understood to be a storm of extraordinary violence, 

 it must be remembered that the gentlest inflow of the air to fill up a vacuum is in 

 kind, if not in degree, identical with the wildest hurricane which levels everything 

 in its tract, but still they differ in some minor characteristics. Thus the great 

 circular storms which destroy such enormous masses of property, and often so 

 many lives, are confined to certain areas, none of which are on the equator as y.t. 

 In America, the Mississippi valley particularly, the broad strip from western 

 Ohio to Colorado is the district which suffers most," (every other State now, 1893,. 

 more or less participates in the climatic disturbances) "and though not confined 

 to any period of the year, the storms are most frequent in April, May, June and 

 July, and on the afternoons of the days rendered memorable by their occurrence. 

 The ordinary whirlwind is to be traced to a thin layer of heat, and therefore at- 

 tenuated air next the ground, which is, however, of top small an extent to pre- 

 cipitate any powerful movement of the atmosphere in its upward whirling. The 

 tornado, which on the other hand, is due (so Farrell, the latest of the tornado in- 

 vestigators, says) to a thick layer of hot, moist air between the earth and the 

 denser upper atmosphere in rising is cooled by expansion, 0nd the invisible vapor 

 with which it is laden condensed, thus liberating a large amount of latent heat."" 

 (Only from deforested and prairie lands). "Tnis latent heat still further rarefies 

 the current of ascending air rushing in on all sides to fill up the vacuum thus cre- 

 ated. In this manner the layer of heated air, owing to its great thickness, causes 

 in its upward movement a correspondingly violent disturbance of the atmospheric 

 equilibrium." (Blind indeed must we be to overlook the fact that a terribly des- 

 tructive " thick layer of hot, moist air between the earth and the denser upper 

 atmosphere," could not exist were the earth's forest lungs thoroughly restored and 

 properly sustained in and around those severely afflicted parts, as the primary hot 

 moist air creating cause would then be greatly diminished besides providing abun- 

 dant leafy absorbing reservoirs to profitably entertain all such vacuum forming 

 air). "But," continues the writer, "whether the storm is the comprehensive 

 cyclone or the narrower but fiercer variety of it, known as the tornado, it is diffi- 

 cult to differentiate between the damage done by the one and that which follows 

 in the train of the other. Little warning is accorded the ill-fated settler of the ap- 

 proach of the winged monster whose appearance drives away every thought save 

 that of flight to some underground cavern" a nice prospect for agriculturists 

 "since few ordinary buildings are strong enough to resist the full impetus of such 

 a wind. Dark and threatening clouds appear in the west, and a lurid or greenish 

 tinge suffuses the sky in the same quarter towards the south, clouds of dust soon 

 follow, concealing the funnel-shaped ckmd in the rear, then, as the tornado nears, 

 an indescribable loud roar is heard. The bellowing of a million of mad bulls and 

 the roar of ten thousand trains have been among the similes suggested, though, 

 perhaps, a continuous roar or rumble of thunder may best describe this dismal 

 forerunner of the storm. But the observer has little time for reverie. In a few 

 moments the funnel-shaped cloud itself follows like a great balloon, sweeping the 

 neck round and round with terrible fury ana destroying everything in its track. 

 In three or four minutes it has passed by, but in that short space of time the 

 staunchest houses of brick and stone have been demolished, and sorrow ard ruin 

 spread all along the path. Indeed, so narrow is this track that in the great tor- 

 nado of last March (1890) the wind in many instances mowed a swath for itself, 

 levelling every building or object in the direct route, but leaving whole or partly 

 uninjured those on either side of the mad rusb. Men, women and children, 

 sheep, cattle, pigs and horses are carried off their feet, and even borue on the 



