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Antique & Scientific Instruments U.K. |
Over
the past few years I have been able to study, in detail, several of
Dancer's microscopes. All of them have been signed on the foot with
the now famous signature J.B.Dancer
Optician Manchester, or
engraved with a more elaborate form in it's
various forms but the basic
instrument (and its case and accessories) has developed through
several stages to the comprehensive binocular
or set which any collector would be proud
to have.
PRE-1850
The
earliest Dancer made (?) microscope I have owned is this one signed
by both Abrahams and Dancer when in partnership at 13 Cross St.,
Manchester (1841 – 1845). This microscope which stands about 13
½ inches high, is typical of the earlier microscopes made
prior to the popularity of the bar-limb designs and was made to be
broken down to
fit into the flat case popular from the middle of the 18th
century. The
finishes are yellow brass lacquer and the bronze finish typifying
Dancer’s accessories over the years to come. As with many sets
made during the early part of the 19th
century, this
set includes a “Bonanni” type stage
which has a
bayonet fitting into
the top of the microscope stage, wheel
of stops condenser which
screws onto the underside of the stage, single sided convex mirror, a
circular live box &
stage mounted bullseye condenser. Course focussing is by thumbwheel
rack & pinion moving the stage up and down the main pillar and
fine focus by thumbwheel screw at the top of the pillar moving the
limb which holds the body tube. The pillar is screwed into the foot
and also has a compass
joint at
the base, for inclining the microscope. Objectives
are early
“button” types mounted on pre-RMS bases to screw into the
body tube which has an external thread to screw into the limb mounted
on the main pillar. The objectives
are screwed
into the cap of the brass can in which they are stored. 2 different
power objectives are present along with 2 different power oculars,
one stored in the corresponding socket in the case and the other in
the body tube. The flat “Y” shaped foot is engraved
“Abraham
& Dancer, Manchester”. The trade
label on
the underside of the case lid, whilst being very similar to Abraham’s
label, is typical Dancer with the exception that it also has Abrahams
name as well as Dancer’s. There are 2 lidded compartments in
the main case. One is a multiple accessory compartment and the other
is a complicated little
case for
holding samples. The main
case which
measures 10 x 8 ¼ x 3 inches is made from fine polished
mahogany with brass hinges and escutcheon for the lock key, but the
lock & key are missing. There is also a space in the top of the
case lid where a brass name plaque once resided.
Early Large Best Microscope
This
large “best” microscope is
from a similar date to the one above but has all the looks of a top
of the range research instrument. The twin handled polished mahogany
cabinet holds all the accessories
in 2 polished mahogany fitted drawers with
ebony button knobs. These include a
watchmakers eyeglass, polariser/analyser, one top hat style wide lens
eyepiece, camera lucida, fishplate, large overstage, small overstage,
1/8, ½ & 2 inch objectives in matching lacquered brass
cans, live box, compressor stage, wheel of stops, forceps, stage
forceps, dark well, illuminator, micrometer & spanner. A further
7 drawers are provided for slides and
storage of other small items. The rectangular section limb has a
swivel joint to allow the optical tube to
be set outside the area of the stage. Main
focus is by rack & pinion using twin wheels, fine
focus is nose-mounted lever type and the draw
tube is engraved to facilitate setting the tube length for each
objective. The instrument has accessories
for both over and under the mechanical stage.
Concentric shafts drive the “Y – Y” movement of the
stage by rotating thumbwheels, the fore/aft drive by both left and
right hand knobs. The bayonet mounted mechanical sub-stage
has an achromatic ”illuminator”. All the objectives are
pre-RMS and the 1/2 inch has a built-on
lieberkuhn. The plano-concave mirror
assembly clamps onto the sub-stage tube with a knurled thumbscrew.
The polariser is bayonet fitted below the stage and the analyser
screws into the bottom of the draw tube. The fine camera
lucida is a tiny speculum mirror on an arm mounted from the
eyepiece and fitted into it’s own lacquered brass can for
storage. The microscope is signed on the
foot Dancer
Manchester. The
trade label on
the inside of the case door has the address as being 13 Cross St.,
which I would date to 1846.
The
first Dancer microscope I
owned was of a good size in a mahogany case with a drawer full of
accessories. Whilst the instrument was
similar in size to later instruments and had the signed "Y"
shaped foot and twin pillar support, the main focus employed the
(earlier) Martin or Drum type microscope
rack & pinion focussing
internal to the main body of the instrument. This used only one
control knob on the side of the microscope
and when the internal rack had
become a little stiff to move, damage to the rack was inevitable. The
case was
of the usual high quality polished mahogany with substantial
lacquered brass handle and held the microscope and free-standing
bullseye condenser in the manner Dancer seemed to favour for the
majority of his microscopes. The accessory case,
however, I have only seen in his
early (1840's & 1850's) microscopes. This is a single large
drawer with lid mounted on it's side in the main case, similar the
style used by Powel & Leyland and Smith & Beck on their most
expensive microscopes. In this single accessory case was fitted a
stage bullseye condenser, ivory or bone handled spike & scalpel,
tweezers, a live box, stage forceps, 4 objectives (one with
Lieberkuhn) all of the pre-RMS thread sizes,
a quantity of slides and a polariser & analyser set.
This accessory set seems
to have employed a particularly neat yet simple storage method using
an external thread on the end of the analyser tube to fix it to a
matching internal thread in the polariser. This saves the necessity
for 2 end caps to keep the dust out of the Nicol prisms, The analyser
screws into the top of an
objective before attaching to the microscope. The poleriser
slots under the stage on a
dovetailed carrier. The trade label
on the inside of the case door
has the address as being 13 Cross St.,
which I would date between 1841
& 1846. However, I understand Dancer was in partnership with
Abrahams form 1841 to 1845, so perhaps this was one of the very first
microscopes Dancer made after the partnership broke up, dating it to
1846. This is how 13 Cross St. looks this
century.
1850'S MICROSCOPE
Into
the 1850's this next instrument is
similar to the one above but the accessory case is fitted out for
different applications. The microscope
itself is similar in size and has the signed
"Y" shaped foot and twin pillar support, the main focus by
internal rack & pinion to the main body of the instrument. A lack
of sub-stage accessories and the extra
lieberkhun would suggest that this microscope was mostly used for
viewing solids or over-stage illumination. The case
is of the usual high quality polished mahogany with substantial
lacquered brass handle and holds the microscope and separate
accessory case. This single accessory case
is fitted with an ivory or bone handled scalpel, brass tweezers, a
live box, stage forceps, a dark ground insert, a locking key and 5
pre-RMS objectives (two with Lieberkuhns). There are a 1/8 and a ¼
button type objectives in brass cans, a 2in. Lieberkhun, a 1in.
Lieberkhun in it's brass can and a dividing
1 ½ to ¾ objective in
a brass can. The trade label on the
inside of the case door has the address
as being 43 Cross St., which I would date to the early 1850's.
The
next development I had was a similar style of microscope but housed
in the multi-drawer case. This seemed to be the next phase in case
development as small blind holes had been let into the back of the
case door to
accommodate the drawer (ebony?) knobs in a very snug fit (or was it
just a mistake on the cabinet maker's behalf?). The trade label,
now at 43 Cross Street, also had to be moved to the inside left panel
of the case to accommodate these holes. Later cases had relatively
shorter drawers obviating the need for the holes in the door. This is
how 43 Cross St. looks this century,
however, I wonder which (if either) of these buildings was Dancer’s
premises? As new buildings were going up in Manchester, the numbering
of buildings were changed to accommodate more individual addresses in
the street. The objectives still had pre-RMS size threads and all the
accessories found
in the single drawer on previous models were available and fitted in
the larger drawers of
this case. The other, smaller drawers
were mostly fitted out to hold
slides on end. It is also interesting to note the workmanship, which
must have been invested in Dancer's free-standing bullseye
condenser which came with this
set. It was a substantial piece. The three-dimensional adjustment was
clamped with thumbscrews and the size was in good proportion to the
microscope it
was to be used with. Another, similar microscope of about the same
era came in an identical case except
for the absence of the blind holes to accommodate drawer knobs. The
drawers on this model were short enough not to interfere with case
door. This case had also seen better days. The microscope was similar
to the previously described two with the notable exception of the
lack of mechanical stage.
This
next instrument is similar to the ones
above but fitted out for polarising applications. The microscope
itself is similar in size and has the signed
"Y" shaped foot and twin pillar support, the main focus by
internal rack & pinion to the main body of the instrument. The
case is of the usual high quality
polished mahogany with substantial lacquered brass handle and holds
the microscope and drawers for accessories
and slides. The main accessory drawer
holds brass tweezers, a compressor / live box, a 1/50 ths stage
micrometer in brass can, a dark ground insert, a RMS to Dancer
objective converter, a Dancer to RMS converter, a pair of polariser
and analysers and 3 pre-RMS objectives. These are a 1/8 and a ¼
button type objectives in brass cans, and a 1in. Lieberkhun in it's
brass can. The smaller accessory drawer
has a sub-stage stop and a cover-correction objective in a brass can.
Cover-correction objectives were introduced to be adjustable for the
varying thickness of microscope slide cover slips, by different
preparers. These were complex and more expensive to make than the
standard fixed focus objective, so were not usually supplied in
microscope sets, so I deduce this one was an “after market”
accessory not fitted into the original case. An un-furnished top
accessory drawer contains a couple of later additions for microscopy.
The trade label on the inside of the case door
has the address as being 43 Cross St., which I would date to the mid.
1850's.
1860'S MICROSCOPE
The
development of binocular or stereo vision through a microscope was
tackled in various ways. The most famous of these being the Wenham
prism, almost universally adopted for half a century. Other attempts
were made, including a three part prism assembly by Dancer. Compare
this with the Wenham prism here. Whereas
the Wenham method used a beam splitting prism to allow binocular
vision through a second eye tube “grafted” onto the side
of a monocular microscope body tube, the Dancer method utilised two
body tubes in a true “V” format.
Each eyepiece receives the same amount of light from the objective.
The Dancer binocular prism method was registered
No 4380 June 27th
1861. This particular microscope
came to me without case or accessories. It is a large stand
at about 18 inches high in use, with the Dancer signature
on the heel of the foot. The main focus is
rack & pinion and fine focus by thumb-wheel operated nosepiece
lever. Inter-ocular separation is by rack & pinion driven by a
thumb-wheel either side of the body tubes. The mechanical stage
has a rack & pinion with thumb-wheel both sides for fore &
aft movement and a single side worm driven lateral control. There is
a female bayonet fitting for sub-stage
accessories but no accessories present. The classical twin pillars
support the assembly above the Dancer tri-form base.
Unusually the base has an arc of heavy brass connecting the front two
“toes”. Perhaps this stand began life as a monocular and
had to have the extra weight added to the front of the base for
balance when the heavier binocular tubes were fitted. This is an
extremely rare and important microscope. I believe only 14 of this
model were made by Dancer, six of which I have been able to track
down, mostly in museums.
A
fine Wenham type binocular microscope in it's fitted case
with a host of accessories, the most
popular Dancer instrument. It is a large stand, about 18 inches high
in use, with the Dancer signature and
number 348 on the heel of the foot dating
to about 1869.
This is an excellent example of the Large Best or No.1 compound
binocular microscope by Dancer. The cast
brass equiaxial foot supports the trunions on the limb by way of a
pair of turned brass tapered pillars. The Wenham binocular body tubes
are focussed by large thumb wheels driving a rack & pinion and
fine focus is by nosepiece levered thumb-wheel. Interocular focus is
by one thumb-wheel driven rack & pinion to the two eye tubes. The
nosepiece houses a shoe containing the Wenham prism and can be slid
into or out of the optical axis to provide binocular or, for higher
magnifications, monocular vision. The mechanical stage has a rack &
pinion with thumb-wheel both sides for fore & aft movement and a
single side worm driven lateral control. The stage has a built-in
socket for sub-stage accessories. A sturdy brass pillar holds the
mirror assembly which comprises a large plano/concave mirror on a “U”
type joint. The microscope comes with a host of accessories
fitted into the top 3 drawers in the
case, including three objectives (¼, ½ cover correction
and a 2 inch) in lacquered brass cans, a pair of low power "top
hat" type eyepieces for binocular viewing and a high power top
hat style eyepiece, a nosepiece polariser, a sub-stage analyser, a
general purpose sub-stage condenser with lever operated iris,
swing-out filter ring and dark ground stop, stage forceps, a few
cover slips and adhesive, forceps and a fine wave
plate . A fine set with rare polarising accessories.
This
particular microscope also came to me
without case. It is a large stand, about 18 inches high in use, with
the Dancer signature and number 382 on the heel of the foot and an
inscription to the first owner(?),
“Arthur Fryer
from Fryer, Benson & Forster24th April 1871.”
This Manchester company were
sugar refiners and patented a process for improving sugar refinement
(perhaps the strange finish on the lacquer is due to the atmosphere
in the sugar refinery in which it was used?). This is an example of
the Large Best or No.1 compound binocular microscope by Dancer. The
cast brass equiaxial foot supports the trunions on the limb by way of
a pair of turned brass tapered pillars. The Wenham binocular body
tubes are focussed by large thumb wheels driving a rack &
pinion and fine focus is by nosepiece levered thumb-wheel.
Interocular focus is by one thumb-wheel driven rack & pinion to
the two removable eye tubes. The nosepiece
houses a shoe containing the Wenham prism and can be slid into or out
of the optical axis to provide binocular or, for higher
magnifications, monocular vision. A Dancer 1 inch objective with can
is present. The mechanical stage has a rack & pinion with
thumb-wheel both sides for fore & aft movement and a single side
worm driven lateral control. The stage has a built-in centring
substage, adjusted by thumbwheels,
holding a removable wheel of stops condenser. A sturdy brass pillar
holds the mirror assembly which comprises a large plano/concave
mirror on an articulated arm. In all a very substantial and usable
instrument.
THE
MANCHESTER FIELD NATURALIST’S BINOCULAR MICROSCOPE
“Manufactured
by the desire of the Committee of the Society” according
to Dancer’s 1873 catalogue. The “society” is now
the Manchester Microscopical Society (of which I am a member) and can
be found at Manchester
microscopical The
microscope is a portable Wenham binocular
instrument which disassembles to fit into it’s case.
It is built on the Ross bar limb style with
the Wenham prism mounted in a shoe to slide
into the body tube. With the prism in line
with the optical axis the microscope works as a low power binocular
and with the prism out of the optical axis the microscope is a
monocular capable of high power magnification. The microscope takes
the RMS standard objectives and has lots
of unusual features. Apparently it was
offered with either rack & pinion main focus or chain
drive. This is chain driven, presumably to reduce weight.
Inter-ocular separation is by a simple (lightweight) lever mechanism,
and the plain stage has a slide bar. The
stage has a central hole threaded to take sub-stage
accessories. Below the stage is a plano-concave mirror.
The microscope is signed on the foot
“J.B.Dancer
Manchester” and
is numbered “26”.
Whilst the inside of the case and drawers are fitted out to take a
host of accessories, sadly the only remaining are a higher power
eyepiece and a nosepiece analyser.
An
antique (economical) Wenham style binocular
microscope, engraved on the
foot J.B.Dancer, Optician, Manchester
in it's mahogany case. The microscope
is based on the Ross “bar-limb” design, and has a flat
“Y” shaped foot with side plates forming trunions to hold
the limb. The main focus is by rack & pinion on the triangular
bar, fine focus by limb mounted thumb-wheel long-lever and
inter-ocular separation is by simple lever and the Wenham prism is
housed in a sliding shoe for both binocular and monocular vision.
Even though this is an “economical” type, it still has a
thumb wheel operated mechanical stage (the upper surface of which is
“engine turned”) with slide bar, a socket to accommodate
sub-stage accessories, and a
plano-concave mirror. The microscope comes with accessories,
including three objectives (¼, ½ and a cover correction
1/5, inch), a pair of low power "top hat" type eyepieces, a
live box and a wheel-of-stops condenser. There is a free standing
bull's eye condenser fitted into the case and forceps in the drawer.
The case has a brass handle to the top, a
door with brass hinges and a working lock with key and has two fitted
drawers, one for accessories and one for
slides. The case also has an unusual Dancer trade label,
on the inside of the door, showing Dancer's prize medal achievements
and stating that he trades “By appointment to Her Majesty's
Commissioners”, dating the instrument to sometime post 1862. A
very usable, “no frills”, binocular microscope.
A
polarising monocular microscope engraved
on the foot J.B.DANCER,
MANCHESTER in
it's mahogany case. This “bar limb”
style microscope has a flat “Y” shaped foot with side
plates forming trunions to hold the limb. The main focus is by rack &
pinion on the triangular bar, fine focus by limb mounted thumb-wheel
long-lever and a thumb wheel operated mechanical stage (the upper
surface of which is “engine turned”) with slide bar, the
underside of which is threaded to take the sub-stage polariser, and a
plano-concave mirror . The microscope comes with several accessories,
including five objectives (¼, ½ ,4 inch & two high
power dividable button types), two "top hat" type
eyepieces, forceps, live box, a sub-stage screw-in polariser
and an analyser which (unusually) screws
into the back of an objective. The case
has a brass handle to the top, a door with brass hinges and a brass
plaque to the front elaborately engraved
“PRESENTED TO John
Riley BY
FRIENDS CONNECTED WITH THE DROYLSDEN INDEPENDENT CHAPEL MAY
1875 DROYLSDEN”.
This instrument looks to be a dedicated petrographic microscope as
the polariser and analyser screw into the instrument and the are no
other sub-stage facilities.
A
fine antique Wenham style binocular
microscope, engraved on the
foot J.B.Dancer, Manchester
and engraved on one of the side plates A
Christmas gift from Joseph Sidebotham, and on the other
To Joel Wainwright, 1883, with accessories in a fitted
mahogany case. Joseph Sidebotham FRAS, was
a prominent member of the Manchester Lit & Phil., a colleague of
Dancers and notable Manchester businessman in the 1800's. The
recipient of this microscope was a protege of Sidebothams and went on
to become a famous author and artist. The microscope
is based on the Ross “bar-limb” design, and has a flat
“Y” shaped foot with side plates forming trunions to hold
the limb. The main focus is by rack & pinion on the triangular
bar, fine focus by limb mounted thumb-wheel long-lever and
inter-ocular separation is by a single thumb-wheel mounted behind the
body tubes and the Wenham prism is housed
in a sliding shoe for both binocular and monocular vision. It has a
plain stage with sliding over-stage and a
socket to accommodate sub-stage accessories, and a plano-concave
mirror. The microscope comes with a host of accessories,
including three objectives (¼, ½ and a dividing 2/1,
inch) in lacquered brass cans, a pair of low power "top hat"
type eyepieces and a pair of high power top hat style eyepieces, a
sliding over-stage & a live box. The sub-stage accessories are a
general purpose condenser with filter ring and lever operated iris
and a wheel-of-stops condenser. There is a free standing bull's eye
condenser fitted into the case and a wet cell, and forceps in the
drawer. The case has a brass handle inset
into the top, a door with brass hinges and a working lock with key
and has two fitted drawers for loose items.
The microscope is in excellent working order with very few cosmetic
blemishes.
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