like in effect the edging
of the clouds at sunset."[474]

This unique phenomenon seemed as if specially designed to accentuate
the inference of a sympathetic relation between the earth and the sun.
From the 28th of August to the 4th of September, 1859, a magnetic
storm of unparalleled intensity, extent, and duration, was in progress
over the entire globe. Telegraphic communication was everywhere
interrupted--except, indeed, that it was, in some cases, found
practicable to work the lines _without batteries_, by the agency of
the earth-currents alone:[475] sparks issued from the wires; gorgeous
aurorae draped the skies in solemn crimson over both hemispheres, and
even within the tropics; the magnetic needle lost all trace of
continuity in its movements, and darted to and fro as if stricken with
inexplicable panic. The coincidence was drawn even closer. _At the
very instant_[476] of the solar outburst witnessed by Carrington and
Hodgson, the photographic apparatus at Kew registered a marked
disturbance of all the three magnetic elements; while, shortly after
the ensuing midnight, the electric agitation culminated, thrilling the
earth with subtle vibrations, and lighting up the atmosphere from pole
to pole with the coruscating splendours which, perhaps, dimly recall
the times when our ancient planet itself shone as a star.

Here then, at least, the sun was--in Professor Balfour Stewart's
phrase--"taken in the act"[477] of stirring up terrestrial commotions.
Nor have instances since been wanting of an indubitable connection
between outbreaks of individual spots and magnetic disturbances. Four
such were registered in 1882; and symptoms of the same kind, including
the beautiful "Rose Aurora," marked the progress across the sun of the
enormous spot-group of February, 1892--the largest ever recorded at
Greenwich. This extraordinary formation, which covered about 1/300 of
the sun's disc, survived through five complete rotations.[478] It was
remarkable for a persistent drift in latitude, its place altering
progressively from 17 deg. to 30 deg. south of the solar equator.

Again, the central passage of an enormous spot on September 9, 1898,
synchronised with a sharp magnetic disturbance and brilliant
aurora;[479] and the coincidence was substantially repeated in March,
1899,[480] when it was emphasised by the prevalent cosmic calm. The
theory of the connection is indeed far from clear. Lord Kelvin, in
1892,[481] pronounced again