262 WEATHER MAKING, ANCIENT AND MODERN. 



wliose fears augmenting as the storm grew fiercer, with clasped hands 

 fastened ui)on the Captain a stare of awe and deprecation. In short, 

 the scene presented a more complete triumph of philosophy over igno- 

 rance than I conld liave supposed it possible to have been produced 

 anywhere in the nineteenth century, and most especially anywhere in 

 our enlightened Eepublic. 



"We often tired the saw-grass marshes afterwards, and whenever 

 there was no wind stirring we were sure to get a shower; and I say 

 with perfect confidence that we never had a shower in April or May at 

 any otlier time. Sometimes when there was a breeze it would carry 

 the smoke toward the horizon, where there would seem to be a fall of 

 rain." 



Espy dwelt on this theory with great devotion, and in 1S45 pub- 

 lished a special letter addressed "To the friends of science,'' in which 

 he proposed a plan for practical rain production. As the paper in 

 question is now very rare and his i^lan possesses some features of inter- 

 est, I quote it here: 



"Let masses of timber to the amount of 40 acres for every 20 miles 

 be i)repared and fired simultaneoiisly every seven days in the sunmier 

 on the west of the United States, in a line of 600 or TOO miles long from 

 north to soutli ; then the following results seem highly probable, but 

 not certain until the experiment is made: A rain of great length north 

 and south will commence near or on the line of tire; this rain will 

 travel eastward; it will not break up till it reaches far into tbe 

 Atlantic Ocean; it will rain over the wliole country east of the place of 

 beginning; it will rain only a short time in any one place; it will not 

 rain again until the next seventh day; it will rain enough and not too 

 much in any one place; it will not be attended with violent wind, 

 neither on land nor on the Atlantic Ocean; there will be no hail nor tor- 

 nadoes at the time of the general rain nor intermediate; there will be 

 no destructive floods, nor will the waters ever become very low; there 

 will be no more oppressive heats nor injurious colds; the farmers and 

 mariners will always know before the rains when they will commence 

 and when they will terminate; all epidemic diseases originating from 

 floods and subsequent droughts will cease; the proceeds of agriculture 

 will be greatly increased, and the health and happiness of the citizens 

 will be much promoted. These, I say, are the probable — not certain — 

 results of the plan i)roposed — a plan which could be carried into oper- 

 ation for a sum which would not amount to half a cent a year to each 

 individual in the United States; a plan, which, if successful, would 

 benetit in ai high degree not merely the landsman, but every mariner 

 that plies the Atlantic. If this scheme should appear too gigantic to 

 commence with let the trial be first made along the Alleghany Moun- 

 tains; and let 40 acres of four 10- acre lots be fired every seven days 

 through the summer in each of the counties of McKean, Clearfield, 

 Cambria, and Somerset, in Pennsylvania; Allegany, in Maryland, and 

 Hardy, rendleton, Bath, Alleghany, and Montgomery, in Virginia. 

 The 10-acre lots "should be, as nearly as convenient, from 1 to 4 miles 

 apart, in the form of a square, so that the up-moving column of air 

 which shall be formed over them may have a wide base, and thus may 

 ascend to a considerable height before it may be leaned out of the per- 

 pendicular by any wind which may exist at the time." 



Espy's theory was i^ractically the modern convective theory of storms, 

 and to this most worthy student of science is due the credit of calling 



