e tail apparently underwent rapid,
frequent, and considerable variations of length. Herschel
discerned symptoms of a rotatory movement both in the comet and
its tail; a movement which carried unequal shreds from the
centre towards the border, and the border towards the centre.
On examining at intervals the same region of the tail--the
border, for example--sensible changes of length must have been
perceptible; which, however, had no reality in them. Herschel
thought that both the comet of 1811 and that of 1807 were
self-luminous. The second comet of 1811 appeared to him to
shine only by borrowed light. It must be acknowledged that
these conjectures did not rest on anything demonstrative.

"In attentively comparing the comet of 1807 with the beautiful
comet of 1811, relative to the changes of distance from the
Sun, and the modifications resulting thence, Herschel put it
beyond doubt that these modifications have something individual
in them,--something relative to a special state of the nebulous
matter. On one celestial body the changes of distance produce
an enormous effect, on another the modifications are
insignificant."

We have reproduced these observations by a distinguished French
astronomer, in order to show the reader what was the nature, and how
great was the importance, of Herschel's labours, and in how remarkable
and comprehensive a manner he conducted his survey of the celestial
phenomena. We now return to our brief narrative of his life.

Such a life, absorbed in tranquil and incessant studies, presents no
curious, romantic, or surprising incidents. It was the life of a
reverent, patient, gentle, and devoted man of genius, who dedicated
himself to the task of making known the "wondrous works of God" to his
fellow-men, and who in all his social and domestic relations was without
blot or stain.

In 1788 he married the widow of John Pitt, Esq., with whom he received
a considerable fortune, and thus for the remainder of his life he was
enabled to give himself up to his favourite pursuits unembarrassed by
pecuniary anxieties. His marriage was in every respect a happy one, and
effectually secured his domestic peace. By his wife he had an only
son,--the late Sir John Herschel,--who worthily maintained the
scientific dignity of his name.

It is said, by the highest of all authority, that a prophet is not
honoured in