Excerpt from the
Pocket Catalogue of Microscopes, Magnifiers,
Microscopical Accessories, Mounting Materials,
etc., James W. Queen & Co., 1892.
ACME No. 3
MICROSCOPE, NEW MODEL.
The entire microscope
is of brass, highly finished, and of the most perfect
workmanship, The body may be set at any angle of
inclination most convenient. The rack and pinion
adjustment has a long range and is of the most
perfect smoothness and delicacy of action. The fine
adjustment is a very delicate and truly-working one,
suitable the highest powers. The body is firmly
carried upon rollers and is moved by a lever actuated
by a screw at the rear of to arm. The head of screw
is graduated.
The stage has complete
rotation. The rotating plate is removable, and an
extra pair of spring clips is furnished to use with
the fixed stage.
The sub-stage is
movable on the mirror bar, is of the gauge most
usually adopted, and carries an adapter having
Society screw. To this is screwed an iris diaphragm,
convenient shaped liked a short objective, for
regulating the amount of light to a nicety. This may
be placed close to the objective, or at
the required distance.
The mirrors (plane and
concave) are also adjustable on the mirror bar; the
mirrors, when in their usual position, rest at the
focal distance of the concave from the object, an
apparent small point, but in reality a very important
one. Mirrors alone or with the sub-stage, may be
swung obliquely, or above the stage. Graduated disk
back of the stage registers the degree of obliquity,
and may be used for the measurement of angular
aperture.
Both the stage and
sub-stage are susceptible of centering adjustments,
by loosening the capstan-head screws which holds them
in position, centering by hand, and tightening again
by a steel key furnished with the instrument. Wear of moving parts is
provided for throughout.
This is an instrument
which we can recommend as being well adapted for work
of even the very highest grade, as, for example,
bacteriological investigations (which require the
highs power lenses, with suitable illuminating
apparatus, and a stand having accurate adjustments
for both.)
Some recent features of
design as applied to this instrument are:
1st a stop, or click, into which the mirror
bar falls when centrally placed; or at zero;
2nd, a knife-edge, or index, for making
accurate reading of scale on fine adjustment screw
head; 3rd, the latter is made with a doubled
milled edge, between which cord may be run for
focusing when the microscope is used for photography
(for which it is well adapted).
The Acme line of
microscopes was first introduced in 1879 by the firm
Sidle and Poalk of Philadelphia. The first microscope
made by the firm was called "The Acme",
an example of which with serial number 17 can be
found on this website. By 1880, the firm was located
in Lancaster Pennsylvania under the name John W.
Sidle & Co. or the "Acme Optical Works".
Subsequently, the entire output of the Acme factory
was consigned to the retailer and manufacturer of
scientific instruments, James W. Queen of
Philadelphia. Five models of the Acme microscopes
were produced numbered 2-6. The No. 3 on this page is
a refined example of the original design.
Elsewhere on this
website is another example of the
Acme No. 3 microscope having a glass
rotating stage with slide carrier and centering
adjustments to the substage. Also see examples of the
Acme models
No. 4 and
No. 5. There are some references in the
literature to an Acme model No. 2, but I have not
been able to locate an actual example of this
microscope.