At the first monthly meeting for the session of the Royal
Meteorological Society, a paper was read by Colonel the Honourable
Arthur Parnell on ‘The Mechanical Characteristics of Lightning
Strokes.’ The main objects of this paper were—first, to attempt to
show that lightning is not a sort of electric fluid that descends
from the clouds, injures buildings and persons in its course, and
dissipates itself in the earth; but that it is a luminous manifestation
of the explosion, caused by two equal forces springing towards each
other simultaneously from the earth and the under surface of the
inducing cloud, and coalescing or flying out nearly midway between the
two plates of the electrical condenser formed by the earth and the
cloud; secondly, to demonstrate that of these two forces, it is the
earth-spring or upward force alone that injures buildings, persons, or
other objects on the earth’s surface, and that constitutes tangibly
what is rightly known as a lightning stroke. The author gave the
details of two hundred and seventy-eight instances, the records of
which were intended to demonstrate with more or less precision the
existence of an upward direction in the force of the stroke. The theory
of the descent of the electric fluid was suggested a few years ago by
M. Colladon, a French Professor, and a notice of it will be found in
_Chambers’s Journal_ for October 16, 1880.