040 BOYS' RADIOMICROMETER (c1910)
THE CAMBRIDGE/ SCIENTIFIC INSTRUMENT CO.LTD./ CAMBRIDGE. ENGLAND./
No. 13345 330H ´ 220D.
Circular brass base with three levelling screws and two bubble
levels; cylindrical brass case with window for indicator beam
and two holes for radiation. Instrument has mirror and thermocouple/coil
on quartz suspension with loop between poles of horseshoe magnet.
IR radiation heats a Bi/Sb thermocouple connected to a single
turn coil of very low resistance suspended between the poles of
a permanent magnet by a quartz fibre. The motion of an attached
mirror deflects a light beam reflected to a distant scale. Boys
invented the 'bow-and-arrow' method of producing quartz fibres
for this instrument. With the aid of a collecting mirror it could
detect heat from a candle flame two miles away but it was unable
to detect heat from any stars or planets.
References:
N.H.
60 MICROSCOPE
Munitions Supply Laboratories, Melbourne.
33H
Black lacquered stand with tilting joint. Fast and slow motion
adjustments on barrel. 16mm and 4mm objectives fitted to turret.
Oil immersion lens missing. x5 and x10 eyepieces. Substage condenser.
Australian made in facillities developed during WWII for production
of gunsights and other military optical equipment. A number of
these microscopes were used for about twenty years in biology
laboratories at UQ.
References:
N.H.
205 PETROLOGICAL MICROSCOPE
E.Leitz, Wetzlar, No. 105906
36*16*13
Black enamelled iron stand supports brass tube carrying two interchangeable
objectives, "2" and "4",and eyepiece lens
. Polarising plates can be slid into the optical path to analyse
the polarisation of the light transmitted by the sample which
can be mounted on a rotating circular brass stage with a graduated
scale. Below the stage is a mirror to reflect light up through
the specimen and a Nicol prism can be swung in to polarise the
light.
Such microscopes are widely used by geologists to examine thin sections of rock as many minerals can be recognised by their characteristic effects on polarised light.
The substage Nicol prism, eyepiece, and one focussing handwheel are replacements fitted when the microscope was restored by Windsor Davies in 1990.
References:
N.H.
052 CONSTANT DEVIATION SPECTROMETER (circa
1920)
Adam Hilger Ltd., London
42*68*60
Cast-iron tripod stand supporting two perpendicular arms holding
a telescope and a collimator respectively. Constant deviation
prism set in line with both arms and lies on a turntable linked
to a marked drum.
The final deviation of light rays through the prism is always 90° and rotating the prism allows different wavelengths to be viewed. The turntable is revolved by a screw to which a calibrated drum is attached, showing the wavelength being viewed. The system must be 'referenced' by viewing some known wavelength (e.g. the sodium lines), setting the drum to the appropriate mark and clamping the prism to the turntable. The collimator eyepiece houses two small lateral slides able to reduce the viewing area to a small rectangle, designed to reduce eyestrain and improve accuracy.
References:
J.C.
053 SPECTROMETER CAMERA (circa 1920)
Adam Hilger Ltd., London
58*24*21
Wooden casing,; brass arm (containing lens), turn screws and clamps.
Photographic plate housing wooden with brass turn screws fro adjusting
plate position. Stiff paper and cloth concertina tunnel connecting
photographic plate housing to wooden casing and brass arm.Also
shutter for exposure. Used with 052 - Constant Deviation Spectrometer
to obtain photograph of the viewed spectrum. Able to be shifted
laterally so as to view the entire spectrum and also vertically
to place one spectrum set above another on the same plate. Can
fit up to 4 sets per plate.
References:
F.G.
057 OPTICAL GONIOMETER (Horizontal - Circle
Goniometer)
R.Fuess, Berlin-Steglitz
24*20*20
Made in Germany approximately 1890's. It is brass and still has
its original lacquered and black enamelled finish. Using a vernier
and slow motion tangent screw, angles can be measured to 1 arcmin
on the graduated scale. The crystal is mounted on the head, which
is adjustable in the x, y and z directions, as well as tiltable
in two axes and rotatable around the third. The collimator is
fixed to the tripod, while the telescope (missing) is movable.
Adjustments critical to the actual measurements are made using
a number of thumb screws below the tripod.
To get accurate measurements, small crystals with smooth faces must be used. The goniometer works on the principle of turning the crystal about an axis parallel to the edge between two faces. The image reflected from a second face may be brought into the same position as that formerly occupied by the image reflected from the first face; the angle through which the crystal has been rotated, as determined by a graduated circle to which the crystal is attached, is the angle between the normals to the two faces.
References:
M.W.
093
THERMOPILE (c.1910)
Griffin, London
24*10D
A circular brass base supports a vertical brass post with a height
adjustment device. Atop the post sits a hollow brass case with
three windows, one with a shutter attachment, and containing a
stack of two types of metal rods. Extended from the top of the
brass case are two electrical connectors.
Visible or infrared radiation beamed into the window with the shutter attachment causes one end of the metal lattice inside the brass case to heat up. Due to the physical properties of the two unlike metals, usually bismuth and antimony (or silver), an electric current will flow from the bismuth to the antimony at the heated end, whilst in the opposite direction at the unheated side. The metal rods are arranged electrically in series so that they produce an electric current great enough to be measured by a galvanometer attached to the connectors.
References:
C.M.
Max Kohl, Chemnitz (c 1920?)
50*50*20
Two polished brass tubes are connected with a rotating joint in a T-configuration. The cross-bar has an eyepiece at one end while the other tube carries a lamp housing on a telescopic section with rack-and-pinion adjustment.
The purpose of the photometer is to make a measurement of a light source's intensity by direct comparison with a known, standard source. The photometer works by an observer making a comparison (with the eye) of the light intensity of two unpolished disks, of which one is movable in the horizontal tube. Enclosed in the perpendicular tube is a Lummer-Brodhun cube consisting of two right-angled prisms which, over a small circular area in the centre of their hypotenuse faces, are in optical contact. Such a cube allows the two illuminated discs to be viewed simultaneously and their brightness compared. The perpendicular tube, which is rotatable, is readily focused onto the light source to be studied. The angle through which the arm is turned is merely read off the mounted graduated arm. A small standard lamp (ideally, 20mm in height including the flame) is utilized, together with the inverse-square law, for comparison of the light intensity. A special mechanism on the photometer allows the height of the lamp to be adjusted.
References: B.K. Johnson, "Practical Optics" - Benn
Bros, London 1922.
WS
113 FLICKER PHOTOMETER (c1912)
Max Kohl, Chemnitz
32*11*20 cm
Contained inside a semi-cylindrical box is a series of rough surfaced
white plates that are placed orthogonally to each other and facing
outwards whilst attached to a wheel. On each side of the box is
a window made of glass and attached to the system is an adjustable
eyepiece with one convex lens which looks through a circular opening
at the white plates.
The procedure of the flicker photometer is that light passes through the glass, striking the white plates and is diffusely reflected through the eyepiece to the observer. The plates are positioned so that they are at an angle of 45o to the windows and aligned alternately so that when the wheel is rotated, the plates reflect light alternately from each window, thus causing a flicker.
The photometer is attached to a sturdy but simple mount that has a well defined angular scale at the opposite end to the eyepiece so the photometer can rotate about an axis passing through the eyepiece. With the whole system made of lacquered and black brass (except the glass windows and lens), it all rests on a simple extendable stand.
Since 1906, flicker photometers have been mainly used and documented for heterochromatic photometry. Being a simple and portable photometer independent of colour difficulty, it is suitable for use in streets and in buildings and for any area where lighting needs to be tested. It can be easily converted to be powered from a constant energy source, such as an electric generator.
References:
J.C.
114 PRISM SPECTROMETER
W. Wilson 1 Belmont St., London, NW
76*32*24
An iron tripod stand supports two arms holding a collimator and
a telescope (both 26 cm in length and at a height of 33 cm) and
a marked turntable (approximately 12 cm in diameter) with a 360o
scale with two vernier scales marked 1 and 2. The collimator can
rotate around the turntable and consists of a lens toward the
prism and at the outer end a slit whose size is regulated by means
of a screw on the left-hand side. The telescope can rotate along
with the scale. The prism table and scale are free to rotate and
the table can be adjusted to be precisely horizontal by means
of three spring mounted screws. The height of the table from the
tripod base is adjustable via a horizontal screw. The turntable
is marked by three parallel lines, seven concentric circles, five
small holes and three small indentations.
Spectrometers are used in spectroscopy for chemical analysis and they paved the way to a previously unimagined branch of physics-astrophysics, which deals with the physics and chemistry of heavenly bodies. Rays of light enter the collimator through a slit, whose size is adjustable to trade off resolution against brightness, and is at the focus of the collimator lens which renders the light parallel before falling onto the prism. The rays undergo refraction and the light gets dispersed into its spectrum which is viewed through the telescope. Angular measurements of the light's deviation are made with the divided circle which reads with a vernier.
References:
B.K.
115 POLARIMETER
Franz Schmidt and Haensch, Berlin, S, No. 8878
85*25*47
Iron stand which supports a sample tube between two Nicol-prisms
- a polariser and an analyser. As monchromatic light passes through
the tube, the plane of polarisation of the light will rotate if
the sample is optically active. A stand is provided for a Bunsen
burner to heat the sample.
The rotation is measured by turning the analyser to match the intensities of two areas with different polarizations, and reading the scale which is provided with two verniers reading to 0.01o.
The amount of rotation is proportional to the concentration of the sample. Therefore polarimeters were used in industries dealing with the production of sugar, starch, jam, condensed milk, wine, oils and drugs.
References:
R.W.
051 BECKMAN DB GT GRATING SPECTROPHOTOMETER (c 1967)
Including Instruction Manual 566-F (dated April 1967)
Beckman Instruments, Inc. Cat. No.: 156801
25*59*36
Metallic housing, with sample placement door at front. Front panel controls for photomultiplier offset and calibration and wavelength selection. Relative absorption read from a meter at front, or may be connected to a chart recorder. 220V, 1A, 50Hz power supply. Ports at the rear allow the circulation of coolant through sample chamber.
Light from either a tungsten lamp (visible) or a hydrogen lamp (UV) is split into two beams. A grating is used to isolate a particular wavelength for study. One beam passes through the sample being analysed and the other is a reference, and the beams are detected by a photomultiplier. A signal is then produced which indicates the relative absorption of that wavelength by the sample. The grating may be set to scan across the available wavelengths at a constant rate and the results recorded by a chart recorder (not present). A coolant circulation system was an optional feature which has been installed on the device (probably added subsequent to purchase).
The primary uses of such a spectrophotometer were biological assays, analysis of biological samples and the study of the rates of production of reaction products in the life sciences. The device on display was in use by the Biochemistry Department at The University of Queensland until 1991 and was certified as serviceable by that department 03/04/90. It appears undamaged and in fair operational order.
References:
1. Harrison Stephens, Golden Past - Golden Future, The First Fifty Years of Beckman Instruments, Inc. Claremont University Centre, 1985.
2. Edisbury, J., Practical Hints on Absorption Spectrometry, Plenum, NY, 1967.
3. Lothian, G., Absorption Spectrophotometry, Hilger, London, 1958.
4. Mellon, M., Analytical Absorption Spectroscopy, J. Wiley, London 1950.
5. Varma, A., CRC Handbook of Atomic Absorption Analysis, Vol. 1, pp.3-37.
6. http://www.beckman,com
MH
EEL International Ltd
45*23*30
A cast - alloy case supports a tungsten lamp, interference filter, sample holder, photo cell, galvanometer and case cover.
Light from the source tungsten lamp passes through the interference filter and samples to the photo cell, then the transmitted intensity is displayed by the galvanometer.
The tungsten-halogen (usually as quartz - iodine) lamp is constructed with a compact tungsten filament. It's advantage is higher energy in the 300-400 nm range.
The interference filter consists of an evaporated coating of layers of transparent dielectrics of alternating high and low refractive index.
The band of wavelengths transmitted varies across the filter so
that wavelength can be scanned from 400-700 nm by moving the filter
sideways using a control knob at the front. This allows the absorption
spectrum of the sample to be roughly judged, or quantitative measurements
of the absorption at a particular wavelength to be made.
References: T. Buckley, N.G. Kents, J. Roberts, J. Wolfenden and
G.A. Woolsey, Instrument maintenance and operation for laboratory
assistants, I.D.P. (1985) p.79-115.
TN
338 COINCIDENCE OPTICAL RANGE FINDER (Entfernungsmesser 14 nr
500S)
Carl Zeiss, Jena
100*10*10
Metal cylinder of about 10 cm in diameter stands on a tripod. Objective lens with rotating cover at each end and eyepiece at centre. Thumbwheel adjustment at right side. This instrument was used to determine the distance to an object with the use of mirrors and lenses.
The coincidence range finder could be summed up as being made up of two simple telescopes separated by a known distance. With a target object located and a range needed, the range finder is adjusted so that the two fields of view from the two telescopes are given in a single field of view. One is inverted in a central window. This view may be observed through the eye piece located at the centre of the range finder. The two images are brought into coincidence horizontally by adjusting a roller geared to a distance scale.
This technology was primarily developed for the use in artillary
in war. With the range to the enemy vital, range finders where
easy to use and fairly accurate. They have also been used in such
things as range finders for cameras as well as particular surveying
jobs.
Reference: E.B. Brown, Optical Instruments, Chemical Publishing
Co., NY, 1945, p.361-370.
AM
341 OPTICAL PYROMETER (c 1940)
Leeds and Northrup Co./Philadelphia USA/Model No. 8622/Serial No.724733
29*17*31
Grey metallic control box containing galvanometer, standard cell, four dry cells, resistors, two slidewires and knobs; connected to a scope by black cable; scope consists of lenses, switch, filament, lamp and a means for focusing.
Current from the cells act upon the set of resistors. One of these, R2, is variable and can be controlled by the use of the large knob on the side of the box. The scale of R2 is calibrated in degrees Celsius, and is carried with its dial. As the resistance is varied, the filament in the scope alters in brightness until it matches the source, leading to the term "disappearing filament pyrometer". Temperature is read directly from the scale.
Designed to be portable, this model is missing the carry strap. It measures a temperature range from 775-2800 degrees Celsius.
References:
1. Directions for No. 8621, No. 8622 and No. 8623 Optical Pyrometers, Leeds and Northup Company, Philadelphia (n.d.)
2. Wood, W.P., Pyrometry, McGraw-Hill Book Co., 1941, pp.114-116.
AK
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