80. — Notices of Tornadoes, §e. 
yards from Chatenay, divided into two parts, one of which disap- 
peared in the clouds, the other in the ground. 
“Tn this hasty account I have, with the intention of returning 
to this portion of the subject, cauited to speak particularly of its 
effect upon trees. All those which came within the influence of 
the tornado, presented the same aspect; their sap was vaporized, 
and their ligneous fibres had become as dry asif kept for forty eight 
hours in a furnace heated to ninety degrees above the boiling point. 
Evidently there was a great mass of vapor instantaneously formed, 
which could only make its escape by bursting the tree in every — 
direction ; and as wood has less cohesion in a horizontal longitu- 
dinal than in a transverse direction, these trees were all, throughout 
one portion of their trunk, cloven into laths. Many trees attest, 
by their condition, that they served as conductors to continual 
discharges of electricity, and that the high temperature produced 
by this passage of the electric fluid, instantly vaporized all the 
moisture which they contained, and that this instantaneous va- 
porization burst all the trees open in the direction of their length, 
until the wood, dried up and split, had become unable to resist 
the force of the wind which accompanied the tornado. In con- 
templating the rise and progress of this phenomenon, we see the 
conversion of an ordinary thunder gust into a tornado ;* we be 
hold two masses of clouds opposed to each other, of which the 
upper one, in consequence of the repulsion of the similar electri- 
cities with which both are charged, repelling the lower towards 
the ground, the clouds of the latter descending and communi- 
cating with the earth by clouds of dust and by the trees. This © 
communication once formed, the thunder immediately ceases, 
and the discharges of electricity take place by means of the cloud: 
which have thus descended, and the trees. These trees, tra 
versed by the electricity, have their temperature, in consequence, 
raised to such a point that their sap is vaporized, and their fibres 
sundered by its effort to escape. Flashes and fiery balls and 
sparks accompanying the tornado, a smell of sulphur remains for 
several days in the houses, in which the curtains are found dis 
colored. Every thing proves that the tornado is nothing else 
than a conductor formed of the qonds, which serves as a 2 ae 
* See 5th vol. of the American Philosopliical Tratisactions, or Silliman’s Jout- 
nal for 1837, ‘vol. 32, page 154. 
Py * 
