12 ANNIVERSARY ADDRESS. 
M. Arago tells us that finding the practice of firing guns common 
in some of the Departments of France, he had tried to trace the 
origin of the custom, which probably began in 1769, It appears 
that a retired naval officer, who at sea had seen waterspouts 
destroyed by cannon shots, made his home in a district that suffered 
from violent rain and hail storms, and he determined to try the 
power of shot and shell upon these new foes ; and setting up his 
battery, he fought his battles o’er again with such success that the 
district was protected from the violent storms—they could not face 
the cannon; and the practice became popular in France, and up t0 
the year 1806, and even later, many Communes kept a battery of 
small guns for this purpose, and the Commune of Fleury even went 
so far as to get a cannon that used a pound of powder for each 
discharge. M. Arago could not trace what the effect had been, but 
he at least was not convinced that it had had any good effect, and 
after a time the practice became obsolete, in spite of the apparent 
success which had given rise to its general adoption. Volta’s 
biographer says that “it is well known that Volta thought 4 
possible advantage might be found in having large fires during 
thunder-storms.” He does not give his reason, but it was probably 
that the smoke of a large fire would serve as a conductor for the 
electricity, and so prevent dangerous discharges. And Arag? 
mentions the fact that near Cesena, Romagna, there is a parish 
which had suffered severely from hail-storms, throughout the extent 
of which, by the Ourd’s advice, the peasants placed, first mounds of 
stone every 50 feet, and on these heaps of straw and brushwoot, 
which they set on fire all over the parish as soon as a storm Wa 
seen approaching, and for three years they had no hail-storms 
while their neighbours, who had no fires, had their crops destroyed 7 
by hail as usual, 
To test the effect of the discharge of artillery on the weathet 
Arago examined the weather record in the Paris Observatory £0" 
many years, especially on and before and after the days on which — 
the regular gun practice took placein the fort situated 3,280 ya 
from the Observatory. The firing took place at this fort on cert? 
