the light takes to
travel from the sun is proved with a simplicity which requires but a
few steps in reasoning. In talking of some inconceivably distant
bodies, he introduced the mention of this plain theorem, to remind
me that the progress of light could be measured in the one case as
well as the other. Then, speaking of himself, he said, with a
modesty of manner which quite overcame me, when taken together with
the greatness of the assertion: 'I have looked _further into space
than ever human being did before me_. I have observed stars, of
which the light, it can be proved, must take two millions of years
to reach this earth.'

"I really and unfeignedly felt at this moment as if I had been
conversing with a supernatural intelligence. 'Nay, more,' said he,
'if those distant bodies had ceased to exist two millions of years
ago, we should still see them, as the light would travel after the
body was gone. . . .' These were HERSCHEL'S words; and if you had
heard him speak them, you would not think he was apt to tell more
than the truth.

"After leaving HERSCHEL I felt elevated and overcome; and have in
writing to you made only this memorandum of some of the most
interesting moments of my life."

CAMPBELL'S conscientious biographer appears to have felt that the value
of this charming account of his interview with HERSCHEL was in its
report of astronomical facts and opinions, and he adds a foot-note to
explain that "HERSCHEL'S opinion never amounted to more than
_hypothesis_ having some degree of probability. Sir JOHN HERSCHEL
remembers his father saying, 'If that hypothesis were true, and _if_ the
planet destroyed were as large as the earth, there must have been at
least thirty-thousand such fragments,' but always as an hypothesis--he
was never heard to declare any degree of conviction that it was so."

For us, the value of this sympathetic account of a day in HERSCHEL'S
life is in its conception of the simplicity, the modesty, the "boyish
earnestness," the elevation of thought and speech of the old
philosopher; and in the impression made on the feelings, not the mind,
of the poet, then thirty-five years old.

In a letter to ALISON, CAMPBELL reverts with great pleasure to the day
spent with HERSCHEL:

"SYDENHAM, _December 12, 1813_.

"MY DEAREST ALISON:--

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