"The manufacture of spectacles, telescopes, microscopes, etc. is carried
on to a great extent in Sheffield. Above five gross per day are ground
of convex and concave glasses in one shop. Concave basins cast in iron
of the radii of curvature of proposed lenses are fixed in rows on a
frame, and rubbed with water and emery. A concentric convex basin is
then covered with round pieces of plate glass fixed with pitch; and the
convex stir face, with its glass pieces, is then turned and _wabbled_
in the concave basin by steam power. In this manner from six to twelve
dozen glasses are ground at once by one basin working within the other
on an eccentric axle which _wabbles_ the inner basin while it is
revolved. Of course, in time, i.e. in eight or ten hours, the glasses
are so abraded, that the outside of one basin exactly fits the other,
and the lenses between are of the true curvature. They are then knocked
off the pitch; turned and worked on the other side, on the second day;
cleaned with spirit of tar, rounded or clipt with blunt scissors, and
fitted in spectacle frames or tubes. In Mr. Cutt's factory I saw
twenty-six of these basins for spectacles, and about eighteen for
telescopes and microscopes; several being at work."
_Fine Arts._
"The Sheffield trades require and promote the Fine Arts in many ways.
Chantrey was a carver and gilder here, and many persons in Sheffield
were his first patrons, when he began to model.
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