had always received from astronomers generally. No individual
observer ever thought of devoting himself to the solar phenomena alone,
while the public observatories confined themselves to merely observing the
sun's culmination at noon, or to ascertaining the exact duration of its
eclipses.

We knew, from the observations of Cassini and Herschel, that the spots on
the sun's disk are not alike numerous every year; and Kunowsky
particularly drew the attention of astronomers to the fact, that while in
the years 1818 and 1819 very large and numerous ones appeared, some
visible even to the naked eye, very few, on the contrary, and those of but
trifling size, were seen in the years 1822-1824. But it was reserved for
the indefatigable Schwabe of Dessau, who has devoted himself for a long
series of years to this one single object, to establish the fact of these
spots observing a certain periodicity. Among the results of his labors--for
as yet we have only his brief announcements to the scientific world in the
"Astronomical Notices"--are the following: 1. That the recurrence of the
solar spots has a period of about ten years; 2. That the number of the
single groups of one year varies at the minimum time from twenty-five to
thirty, while in the maximum years they sometimes rise to above three
hundred; 3. That with their greater abundance is combined also a greater
local extension and blackness of the spots; 4. That at the maximum time,
the sun, for some years together, is never seen without very considerable
spots. The last maximum appears to have been of a peculiarly rich
character, as, from February, 1837, till December, 1840, solar spots were
visible on every day of observation; while the number of groups in the
former of those years amounted to 333.

But if a single individual, by observations continued unbroken for entire
decenniums, has thus revealed to us the most important fact hitherto known
relating to the sun, there are other questions not less important which
can only find their solution in the careful observation of a
rarely-occurring interval of perhaps one or two minutes. The splendor of
the sun is so amazingly great, as to preclude us entirely from perceiving
any object in his immediate proximity unless projected before his disk as
a darkening object. At ten, or fifteen degrees even from the sun, when
this luminary is above the horizon, all the fixed stars vanish from the
most powerful telescopes. We are therefore