He obtained the means of testing this prediction when
he completed a superb circle for Palermo of five feet diameter.
Finding his anticipations were realised, he desired to apply the same
principles on a still grander scale. Ramsden was in this mood when
he met with Dr. Ussher. The enthusiasm of the astronomer and the
instrument-maker communicated itself to the Board, and a tremendous
circle, to be ten feet in diameter, was forthwith projected.
Projected, but never carried out. After Ramsden had to some extent
completed a 10-foot circle, he found such difficulties that he tried
a 9-foot, and this again he discarded for an 8-foot, which was
ultimately accomplished, though not entirely by himself.
Notwithstanding the contraction from the vast proportions originally
designed, the completed instrument must still be regarded as a
colossal piece of astronomical workmanship. Even at this day I do
not know that any other observatory can show a circle eight feet in
diameter graduated all round.
I think it is Professor Piazzi Smith who tells us how grateful he was
to find a large telescope he had ordered finished by the opticians on
the very day they had promised it. The day was perfectly correct; it
was only the year that was wrong.
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