Some tranfparent objedls appear to the greateft advantage when
the lens at 9 and to is taken away; as, by giving too great a
quantity of light, it renders the edges lefs fharp.
The variety o f views which may be taken o f every objeft, by
means o f the improved lucemal microfcope, will be found to be
o f great ufe to an accurate obferver: it will give him an opportunity
o f correfting or confirming his difcoveries, and invefti-
gating thofe parts in one mode, which are invifible in another.
T o THROW THE IMAGE OF TRANS PARENT OBJECTS ON A
Screen, as in the Solar M icroscope.
It has been long a microfcopical defideratum, to have an in-
ftrument by which the image of tranfparent objecls might be
thrown on a fcreen, as in the common folar microfcope; and
this not only becaufe the fun is fo uncertain in this climate, and
the ufe o f the folar microfcope requires confinement in the fineft
part o f the day, when time feldom hangs heavy on the mind, but
as it alfo affords an increafe of pleafure, by difplaying it’s wonders
to feveral perfons at the fame inftant, without the leaft fatigue to
the eye.
This purpofe is now effeftually anfwered, by affixing the tranf-.
parent ftage of the lucernal to a lanthorn, with one of Argand’s
lamps.— The lamp is placed within the lanthorn, and the end 9,
10 o f the tranfparent ftage is fcrewed into a female fcrew, which
is rivetted in the Hiding part o f the front o f the lanthorn ; the
magnifying lenfes are to be fcrewed into the hole reprefented at
12; they are adjufted by turning the milled nut. The quantity
of
of light is to be regulated, by raffing and lowering the fliding-
plate, or the lamp. N. B. This part, with it’s lanthorn and
lamp, may be had feparate from the lucernal microfcope.
A pparatus which Usually accompanies the improved
L ucernal M icroscope.
The ftage'for opake objefts, with it’s femicircular lump o f
glafs, and concave mirror.
The ftage for tranfparent objects, which fits on the upper part
o f the foregoing ftage.
The Hiding tube, to which the magnifiers are to be affixed;
one end of thefe is to be fcrewed on the end B o f the wooden
body; the magnifier in ufe is to be fcrewed to the other end of the
inner tube.
Eight magnifying lenfes; thefe are fo con drafted, that they
may be combined together, and thus produce a very great variety
o f magnifying powers.
A fiffi-pan, fuch as is reprefented at L Plate IX.
A Heel wire L , with a pair of nippers at one end.
A fmall cylinder of ivory 1 at the other.
A Aider of brafs N, containing a flat glafs Aider, and a brafs
Aider, into which are fitted fome fmall concave glaffes.
A pair