Microscope arranged with the condenser for viewing transparent objects.
Microscope arranged with the Lieberkuhn and stage forceps for viewing opaque objects.
The limb can be removed and converted to a compass
microscope using the Lieberkuhn objective with the stage forceps.
A view through the microscope
of a preparation between mica disks on the ivory
The microscope now
known as the "Jones Improved" model has its origin in
the a microscope introduced by George Adams Jr.
in the late 18th century and described in his 1787
publication, Essays on the Microscope. By the end of
the century, the copyright to Adams' books and
designs were purchased by the firm W. & S. Jones
of London. They began, in 1798, the production of a
microscope with a similar design, which they called
the "Jones Improved Microscope". A rectangular pillar
which is usually mounted on a box with a draw
characterizes this design. Mounted on the top of
pillar is a bar that holds the tube, while on the
pillar is mounted the stage and the mirror. The
focusing mechanism consists of a rack embedded in the
pillar an pinion attached to the stage; this
arrangement moves the stage in and out of focus. The
mirror can also be positioned on the pillar by
sliding it up and down. The optics in this model
usually consist of a double eye-lens and a field lens
located within the body of the tube; the objectives
are non-achromatic. This design became very popular
and was produced by many other English opticians
during the first part of the 19th century. It was
supplied with a variety of accessories as illustrated
in the image at the right taken from the Adams