Page 73 - James Rodger Fleming - Fixing the sky

failing to receive, government support for rainmaking. “Magnificent Humbug”
opined the Genesee Farmer. According to the Boston Quarterly Review, “The pub-
lic at large think of him as a sort of madman, who fancies that he can produce
artificial rain.” 12
Espy’s magnum opus, The Philosophy of Storms (1841), includes a long section
titled “Artificial Rains,” in which he compiled testimonies of rainfalls accompa-
nying volcanic eruptions and large fires: “The documents which I have collected
on this subject, if they do not prove that the experiment will succeed, do at least
13
prove that it ought to be tried.” Espy concluded that if a large body of air is
forced to ascend in a column, a large self-sustaining cloud will be generated and
cause more air to rise up into it to form more cloud and rain. He argued that this
was certainly the case in volcanic eruptions and should also be the case for great
fires. He cited the mysterious connection between volcanoes and rain as noted
by the famous geographer and explorer Alexander von Humboldt, who observed
that sometimes during a volcanic eruption a dry season changed into a rainy one.
Thus he argued that the rainmaking effects of a giant forest fire should mimic
those of a volcanic eruption.
Espy scoured the literature for supporting evidence. He cited Martin Dobri-
zhoffer, an Austrian Jesuit evangelist in South America who wrote that he wit-
nessed the tribes of the Abipones in Paraguay producing rain (in an admittedly
very rainy climate) by setting fire to the plains. He also cited the practice of
American Indians burning the prairies to produce rain, and he called for his cor-
respondents to send in reports and testimonies of similar instances supporting
his theory. An observer in Louisiana wrote that a conflagration in the long grass
in the prairies of that state was soon followed by rain.
In 1845 Espy issued a circular letter “To the Friends of Science” with
specific details of his rainmaking plan. He proposed a massive experi-
ment along the Alleghany Mountains (a region quite familiar to him): “Let
forty acres . . . be fired every seven days through the summer in each of the
counties of McKean, Clearfield, Cambria, and Somerset, in Pennsylva-
nia; Alleghany in Maryland; and Hardy, Pendleton, Bath, Alleghany, and
Montgomery, in Virginia.” Espy anticipated the effects of upper-air wind
shear by recommending that woodlots several miles apart be fired, “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 perpendicular by any wind which may exist at
the time.” 14
He also proposed an even larger, continental-scale project that involved
simultaneously firing masses of timber in the amount of 40 acres every 20 miles,

56 | rain makerS