orms, are
confessedly, and in proportion to their intensity, "_highly electric_."
This excess of quantity or activity of electricity, exists in connection
with the movable atmospheric machinery. When it moves up north in summer,
and arrives at its highest point of northern transit, _storms_ are very
_uncommon_, and the tropical forms of cloud and showers, with thunder and
lightning, prevail. This is most obvious, if not most influential, where
the magnetic intensity is greatest. Violent showers, and gusts, and
tornadoes, are more frequent in this country than in Europe; and over the
area of greatest intensity, as in Ohio, than at a distance on the extreme
eastern or western coast. And the same is true over the intense magnetic
area of Asia.

Electricity, too, like magnetism, has its diurnal, and doubtless its
annual and decennial variations, and also its irregular ones, and they are
most obviously and intimately connected. Magnetism and electricity
together, constitute the aurora. Its culmination is in the magnetic
meridian--it affects the telegraph wires--is connected with the irregular
disturbances which affect the magnetic needle, and does not exist in the
limits of the trades, although occasionally seen from thence, when it
passes south, and near them.

The aurora sometimes extends south in waves, as do the magneto-electric,
atmospheric, periodical changes of cold and heat, and storm, and sunshine.
_The aurora is connected with the formation of cloud_, and with a smoky
atmosphere, similar to that with which we are familiar in summer and
autumn. Thus Humboldt (Cosmos, vol. i. pp. 191, 192).

"This connection of the polar light with the most delicate cirrus clouds,
deserves special attention, because it shows that the electro-magnetic
evolution of light is a part of a meteorological process. Terrestrial
magnetism here manifests its influence on the atmosphere, and on the
condensation of aqueous vapor. The fleecy clouds seen in Iceland, by
Thienemann, and which he considered to be the northern light, have been
seen in recent times by Franklin and Richardson, near the American north
pole, and by Admiral Wrangel on the Siberian coast of the Polar Sea. All
remarked 'that the aurora flashed forth in the most vivid beams when
masses of cirrus-strata were hovering in the upper regions of the air, and
when these were so thin that their presence could only be recognized by
the formation of a halo round the moon.' These cloud