rose

Charles Burney

The Present State of Music in France and Italy (2nd, corrected edition)

London: T. Becket and Co., 1773

Naples
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but especially in microscopes, by means of
a very small drop or globule of pure
crystal glass, the smaller the better.
He melts the glass himself in a vessel of
Tripoli earth, and renders it spherical
in a clear flame. It magnifies the dia-
meter of an object, if the globule be of
the smallest class, 2560 times; the com-
mon microscopes only magnify about
350 times *. After shewing me the
whole process, he was so obliging as to

* The discovery is not new; Leeuwenhoek is
said to have used little spheres of glass in his micro-
scopes; Mr. Baker indeed treats them with contempt:
and says, "Experience has taught, that they ad-
" mit so little light, can shew such an exceedingly
" small part of any object, are so difficult to make
" use of, and strain the eyes so much, that their
" power of magnifying for want of due distinct-
" ness, is rather apt to produce error than disco-
" ver truth." Microscope made easy. But however
true this might have been at the time Mr. Baker
wrote, Padre della Torre seems at present to have
got the better of every objection to these glass
globules by the dexterity with which he forms and
uses them.
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