From: Behrens
Guide to the Microscope in
Botany, 1885
This stand, made by the
Bausch and Lomb Co., is represented 1/2 natural size in
Plate XI. It comprises the same general features as the
one last named, but by a slight increase of distance
between the stage and the table sufficient space is
secured to admit the use of the largest illuminating or
polarizing apparatus, etc., that is usually employed on
the largest stands. In fact there is scarcely any of
the accessory apparatus of the highest-priced
microscopes that cannot, with a few slight
modifications in non-essential particulars, be easily
and efficiently combined with this. This stand can be
obtained as shown in the cut, in a very simple and
inexpensive style; but it is capable of a much higher
development. It has been constructed, for the use of
the writer, with the addition of lengthening mirror
bar, graduated draw-tube for use in micrometry and in
drawing to scale at any desired amplification,
centering adjustment to stage, and graduated rotation
of the same, centering substage moved vertically with
rack and pinion, and graduated fine adjustment screw
with index point, for use in measuring approximately
the thickness of objects or cover-glasses. It is named
by the makers the "Universal," from the belief that it
is possessed of the working capacity of the most
elaborate stands. The stage is well adapted to the use
of a glass sliding stage; and a mechanical stage moved
in all directions by special mechanism can be added if
desired.
From the B&L Price list, 7th ed., 1882:
Bausch and Lomb Optical
Co.'s Glass Stage and Slide-carrier.This (Fig. 128)
is intended as a substitute for the mechanical stage
to a certain extent. It consists of a polished plate
of glass, incased in a brass ring, which clamps on
the circular stage. The slide-carrier, which moves on
it, consists of a light metallic plate, and has
protruding from its lower surface four small points;
at its two ends are prolongations, which are bent
downward and inward, and, acting as springs, press
against the lower surface of the glass. As the
contact between glass stage and slide- carrier is
only in these six points, friction is reduced to a
minimum, and the action of the latter, although firm,
is smooth and steady. It is claimed that it enables
work to be done with far more facility than in the
ordinary brass stage, where the entire surface of the
slide bears on it, and that it is altogether more
agreeable. The slide- carrier is provided at each end
with small milled heads for manipulation, and has
spring clips and a stop for Maltwood finder.
From the
Journal of the Royal Microscopical
Society.
Bausch and Lomb
Optical Co.'s Fine
Adjustment. Fig. 126 represents the original
of the fine-adjustment referred to at Vol. I. (1881)
p. 110. Two strong parallel blades of finely tempered
steel, a a, are securely fastened on one end to the
back of case Fig. 126. d, on the other to the arm e,
which carries the rack and pinion, b shows the
micrometer screw, which is fitted to the upper part
of the upright arm c, f is the pinion, g the
rack and slide, h the tube. Two screws fasten the
adjustment case d to the pillar c. An arm projects
from the part e and passes into a recess in the
pillar c. The springs support the entire body, and as
their tension is upward, the projecting arm bears
continually against the micrometer screw b, and it is
evident that tho distance traversed by tho screw
involves the same movement of the arm e, and
consequently the body. The only points of contact are
at the ends of the springs a, a, where they are
fastened respectively at d and e, and on the
micrometer screw, and as in the former there is
absolutely no friction, there is no wear; while that
which may eventually take place in the latter is
taken up by the force of the springs.The points of
excellence claimed by the makers for this adjustment
over all others, are the following: 1. It moves the
entire body. 2. It is extremely sensitive and direct.
3. It has no lateral motion or displacement of the
image, while adjusting. 4. It has absolutely no lost
motion. 5. It can in no manner deteriorate.
An 1889 Bausch
& Lomb advertisement