The following was extracted from the 1875 Ross catalog:
No. IA Binocular Microscope Stand (I) with two eye-pieces,coarse and fine adjustments for focussing, graduated concentric rotating stage, having 1-inch of rectangular motion, rack and screw movements, clamping lever, graduated sub-stage for holding and adjusting illuminating and polarizing apparatus, diaphragm plate, plane and concave mirrors, and WENHAM’S Binocular arrangement.
The microscope is furnished with an example of
the Ross improved Gillett achromatic condenser.
It is marked: Ross 2053,
London. It has two diaphragm disks that can
be used in combination where each is controlled by a
milled knob. The upper disk has conventional
graduated apertures while the bottom disk has
apertures for dark field and oblique illumination.
Compare this with the
earlier form of the Gillett condenser.
No.1 Improved
Binocular Microscope Stand.
Ross' Model (1),
with two eye-pieces, coarse and fine adjustments
for focusing, graduated concentric rotating
stage, having 1 inch of rectangular motion, rack
and screw movements, clamping lever, graduated
sub-stage for holding and adjusting illuminating
and polarizing apparatus, diaphragm plate, plane
and concave mirrors, and Wenham's Binocular
arrangement
No.1A
Improved Binocular Microscope
Stand.
Designed by Wenham,
on Jackson's Model (2), with two eye-pieces,
coarse and fine adjustments for focusing,
graduated concentric rotating stage, having 1
inch of rectangular motion, rack and screw
movements; clamping lever, graduated sub-stage
for holding and adjusting illuminating and
polarizing apparatus, diaphragm plate, plane and
concave mirrors, and Wenham's Binocular
arrangement.
Remarks on the Binocular Microscope by F.
H. Wenham
See: Ross
of London chronology by T. Wayland