ill in
full credit.

An instance of the same kind was observed by Mr. W. R. Birt in
1860,[407] and cyclonic movements are now a recognised feature of
sun-spots. They are, however, as Father Secchi[408] concluded from his
long experience, but temporary and casual. Scarcely three per cent. of
all spots visible exhibit the spiral structure which should invariably
result if a conflict of opposing, or the friction of unequal, currents
were essential, and not merely incidental to their origin. A whirlpool
phase not unfrequently accompanies their formation, and may be renewed
at periods of recrudescence or dissolution; but it is both partial and
inconstant, sometimes affecting only one side of a spot, sometimes
slackening gradually its movement in one direction, to resume it, after
a brief pause, in the opposite. Persistent and uniform notions, such as
the analogy of terrestrial storms would absolutely require, are not to
be found. So that the "cyclonic theory" of sun-spots, suggested by
Herschel in 1847,[409] and urged, from a different point of view, by
Faye in 1872, may be said to have completely broken down.

The drift of spots over the sun's surface was first systematically
investigated by Carrington, a self-constituted astronomer, gifted with
the courage and the instinct of thoughtful labour.

Born at Chelsea in May, 1826, Richard Christopher Carrington entered
Trinity College, Cambridge, in 1844. He was intended for the Church, but
Professor Challis's lectures diverted him to astronomy, and he resolved,
as soon as he had taken his degree, to prepare, with all possible
diligence, to follow his new vocation. His father, who was a brewer on a
large scale at Brentford, offered no opposition; ample means were at his
disposal; nevertheless, he chose to serve an apprenticeship of three
years as observer in the University of Durham, as though his sole object
had been to earn a livelihood. He quitted the post only when he found
that its restricted opportunities offered no farther prospect of
self-improvement.

He now built an observatory of his own at Redhill in Surrey, with the
design of completing Bessel's and Argelander's survey of the northern
heavens by adding to it the circumpolar stars omitted from their view.
This project, successfully carried out between 1854 and 1857, had
another and still larger one superposed upon it before it had even begun
to be executed. In 1852, while the Redhill Observatory was in course of