This section is further sub-divided
into following sections:
108.1 Plain Mirror Glass : Back silvered, with protective coatings & ground edges.
| Type | A | B | C |
| Size | 75 x 25 mm | 150 x 25 mm | 150 x 50 mm |
108.3 Circular Mirror : Plane, circular, ground edges, 50 mm diameter. Back silvered with protective coating.
108.4 Plain Mirror Glass - Mounted : Same as 108.01 but mounted on wooden block approx. 20 mm thick.
108.5 Cylindrical Mirror, Concave : Semicircular mirror, 150 mm dia x 25 mm height. Made of stainless steel.
108.6 Cylindrical Mirror, Convex : Same as in 108.05 - a convex mirror
108.7 Concave Mirrors : Optically worked, back silvered, with protective coating.
| Type | A | B | C | D | E | F |
| Focal Length (mm) | 75 | 100 | 150 | 200 | 250 | 300 |
| Diameter 50 mm | 75 | 100 | 150 | 200 | 250 | 300 |
| Diameter 75 mm | 75 | 100 | 150 | 200 | 250 | 300 |
108.8 Convex Mirrors : Optically worked, back silvered, with protective coating.
| Type | A | B | C | D | E | F |
| Focal Length (mm) | 75 | 100 | 150 | 200 | 250 | 300 |
| Diameter 50 mm | 75 | 100 | 150 | 200 | 250 | 300 |
| Diameter 75 mm | 75 | 100 | 150 | 200 | 250 | 300 |
108.10 Lenses, Set of Six : Same as 108.09 but with diameter 75 mm.
108.11 Lens, Double, Concave, Spherical : Optically worked, ground edges
| Type | Diameter | Focal Length |
| A | 50 mm | 50 mm |
| B | 50 mm | 100 mm |
| C | 50 mm | 150, 200, 250, 300, 500, 1000mm |
| Type | Diameter | Focal Length |
| A | 50 mm | 50 mm |
| B | 50 mm | 100 mm |
| C | 50 mm | 150, 200, 250, 300, 500, 1000mm |
| Type | A | B | C | D |
| Focal Length | 60 mm | 75 mm | 100 mm | 150 mm |
| Type | A | B | C |
| Focal Length | 60 mm | 150 mm | 300 mm |
| Type | A | B | C |
| Focal Length | 60 mm | 150 mm | 300 mm |
| Type | A | B | C |
| Focal Length | 70 mm | 150 mm | 200 mm |
108.18 Lens Holder : Comprising a metal holder with sides grooved to hold the lens or mirror. The holder is finished in matt black & is free standing for bench use, to hold lens 50 mm in diameter.
108.19 Spherometer : Brass dial head 40 mm diameter with stainless steel screw 0.5 mm or 0.1 mm pitch, head divided in 100 divisions, reading to .001 mm or .005 mm & registering on vertical scale10-0-10 mm frame with feet of stainless steel on p.c.d. of 46 mm. Separation approx. 40 mm. Zero adjustment can be done by unscrewing thumb screw.
108.20 Glass Block, Rectangular : Without bubbles, made from sheet glass, all sides polished.
| Type | A | B |
| Size | 75 x 50 x 18 mm | 115 x 60 x 18 mm |
108.22 Perspex Block, Rectangular : Rectangular of clear perspex, al faces fully polished. Size 115 x 60 x 20 mm approx.
108.23 Perspex Block, Semicircular : Of clear perspex, all faces nicely polished 80 mm dia & 20 mm thick approx.
108.24 Prism Glass, Equilateral : Made from moulded glass, equilateral
| Type | A | B | C |
| Size | 25 x 25 mm | 38 x 38 mm | 50 x 50 mm |
| Type | A | B |
| Size (Height) | 38 mm | 50 mm |
| Type | A | B |
| Size | 25 x 25 mm | 38 x 38 mm |
| Type | A | B |
| Size | 25 x 25 mm | 38 x 38 mm |
Borosilicate Crown Glass 1.51 R.I. App.108.29 Glass Cube, Hollow : Made of optically flat plates cemented together. Dimensions 50 x 50 x 50 mm.
Dense Flint Glass 1.62 R.I. App.
Extra Dense Flint Glass 1.65 R.I. App.
Double Extra DenseFlint Glass 1.70 R.I. App.
Type A B C Size 25 x 25 mm 38 x 38 mm 50 x 50 mm
108.30 Hollow Prism :
Hollow Prism 38 x 38 mm108.31 Set of Acrylic Plastic Blocks : Clear acrylic plastic blocks 20 mm thick; all sides & surfaces fully polished. The set comprises 7 blocks as follows
Hollow Prism 50 x 50 mm
Hollow Slabs 75 x 50 x 18 mm
Trough 60 x 60 & 75 x 75 mm
Rectangle 75 x 50 mm
Triangle 90º x 45º x 45º; 75 mm hypotenuse
Triangle 60ºx 60º x 60º; 57 mm side
Semicircle 75 mm diameter
Bi Convex 75 mm long, curved faces radius 115 mm
Bi Convex 75 mm long, curved faces radius 145 mm
Bi Concave 75 mm long, curved faces radius 115 mm
108.32 Optical Disc, Magnetic : 500 mm diameter, steel disc is faced with matt white, marked every 5º, with extended lines every 10º & 30º; cross lines mark the centre. The disc is mounted on a 25 mm diameter steel tube 390 mm long which fits into a stable base with levelling feet. The disc rotates about its centre & can be locked in any desired position. The lamp house holds a 12V, 24W axial filament lamp. This lamp house is covered by a rotatable outer shield that has various slots. By rotating the shield, light beams of varying width as well as narrow single, double & triple beams can be provided. Attached to the lamp house is an adjustable lens carrier with lens to provide diverging, parallel or converging light beams. The lamp house is mounted on a rotatable arm that can be locked in any position. A sliding weight on the arm acts as a counterpoise. All optical elements are supplied with magnets attached so that they can be attached at any place on the disc. The disc is supplied complete with accessories.
108.33 Refractive Index of a Liquid by Critical Angle Method : The apparatus consists of a metal bridge 130 x 90 x 80 mm, fitted with anti slip rubber edging strips. The air cell holder is attached to a large knob & scale. Graduated 0 - 360º. The air cell takes the form of two flat glass plates, 50 x 50 mm; arranged parallel & at a small distance apart in a sealed masking frame. Liquid under investigation is contained in a transparent perspex tank. Supplied with tank.
108.34 Ray Optics Box : Black finish metal box, with 12V 24W straight filament lamp. The lamp holder, with 1m of twin flex, is mounted in sliding metal bridge piece which provides sufficient adjustment to covering, parallel or diverging rays. The enamelled steel body has slots to support a cylindrical lens & a triple slit screen. Extra slots are provided for filters. Dimensions 182 x 61 x 115 mm. The box is supplied complete with lamp & triple slit but without lenses or filters.
108.35 Ray Optics Kit : Kit consists of two lamp holders, each in metal shade with two axial slots & mounted on metal support rod. Holder complete with approx. 1.2m 2 wire P.V.C. covered cable & 12V 24W axial filament lamp. One each right & left hand cylindrical lamp shields, in matt black ‘combs’; with 17 equi spaced parallel slots, Two black plastic plates, each with single & triple slits, two comb & plate holders, a spring loaded clip mounted on metal support bracket, 4 metal light barriers, 4 each plano convex cylindrical lenses, 50 x 50 mm, +7D, two each cylindrical lenses 50 x 50 mm respectively, plano convex +10D, +17D, plano concave -17D.
108.36 Ray Optics & Colour Mixing Box : The metal box is double ended so that two sets of students can work independently with the same box. Slide apertures are provided which accommodate colour filters for colour mixing experiments & have blinking plates for when the slide apertures are not in use. The box is provided with a 12V 24W straight filament lamp fixed at the centre of the apparatus while at each end is a sliding grooved frame to carry a convex cylindrical lens together with slit screen &/or filter. Long clear tracks. To triple slit screen, two blank plates for closing side aperture when not in use & 1m of twin flex. Dimensions 308 x 63 x 115 mm high supplied without lenses, filters or other accessories.
108.37 Ray Track Apparatus : A compact visual teaching aid which is robust in construction wood board 400 x 280 x 13 mm with matt white surface, mounted on rubber feet carries a circular scale with four quadrants 0 - 90º graduated every 2º, with two lines at right angles. The ray box is provided with slots to accommodate metal slits, colour filters, lenses etc., & is fitted with a 12V 24W line filament.
108.38 Pin Hole Camera : Two rectangular, open ended, light proof wood boxes. One slides into the other & contains a frosted translucent glass plate upon which image is formed. The other box has a pin hole opening at the closed end. Dimensions 150 x 100 x 100 mm approx. Also available as a kit.
108.39 Telescope Model, Astronomical : Comprising a convex lens 38 mm diameter & 150 mm focal length, mounted in a plastic tube 400 x 50 mm diameter, & a double convex lens 50 mm diameter & 500mm focal length, mounted in a tube 400 x 55 mm diameter. The smaller tube is located in the large tube my means of foam plastic rings which provide an effective sliding light seal.
108.40 Telescope Model, Terrestrial : Same as 108.39 but with plano concave eye piece lens to provide erect image.
108.41 Astronomical Telescope : Reflecting type, fitted with about 45 mm dia achromatic objective having focal length of about 450 mm. Focusing is provided by rack & pinion. Complete with carrying case with the metallic three legged folding type tripod stand.
108.42 Reading Telescope : Designed for general laboratory work. The telescope is mounted on 18 mm diameter, pillar 450 mm long fitted on a heavy tripod base. The telescope can be rotated both in vertical as well as horizontal plane. It is fitted with 180 mm focus achromatic object with 25 mm clear aperture , 10x ramsden eye piece with cross wire. The telescope is focused by rack & pinion & has a range from one meter to infinity; with perspex scale & its attachment.
108.43 Reflecting Telescope : A high quality instrument with a resolving power of 1.5 seconds. The 100 mm (4 inch) diameter, 1000 mm focal length mirror gives relatively more light & less chromatic aberration than an equivalent refractor. Magnifications of upto 250x are obtainable. The telescope has an equatorial mount with hour and declination circle & micro adjustments with flexible connections to avoid vibrations. The whole is mounted on a heavy 1.52 m tripod with an accessory tray. Supplied complete with two interchangeable eye lenses 6 mm & 20 mm, a 2x Barlow lens, sun filter, moon filter, a 5x24 star finder telescope (with mount on main telescope body), a solar aperture cap & an instruction booklet with space & moon maps.
108.44 Optical Bench 1 Meter, Wooden : Comprising a wooden base board 1100mm x 115 mm with one meter scale divided in mm & figured at every cm fixed along the front edge & complete with following accessories : Two white faced object & receiving screen, one plane mirror 150 x 100 mm, 4 lens holder V shaped, one needle mounted vertically in a short wooden rod in the centre of a wooden base. The optical centre height of all the components is 100 mm above the base board.
108.45 Optical Bench 1.5 Meters : Comprising a wooden base board 1600mm x 140 mm with a 1.5 meter scale divided in mm plus six sliding moulded metallic bases 100 x 50 mm each with engraved line, brass pillar with screw for locking. Accessories : one 240V white lamp with lamp house; 1 metal object white screen 75mm diameter with gauze; 1 metal object white receiving screen 100 x 75 mm; 1 needle mounted in rod 6 mm; 1 plane mirror 100 x 75 mm. All the accessories mounted on a 6mm brass rod which fits in a stand giving an optical height of approx. 125 mm above the base board.
108.46 Optical Bench 1 Meter : One meter long, for advanced research work; consists of two rods, one stainless steel & one chrome plated steel. The stainless rod is divided in mm. These are supported on heavy cast iron feet with levelling screws. Four specially designed metal sliders having a fine index mark enables reading to be taken on scale with ease & accuracy. The sliders are machined metal so they slide accurately & smoothly on the bed. Two of the sliders have transverse slow motion adjustment. Complete with 6 accessories ( 2 lens holders, 2 optical pins, 1 candle holder, & 1 screen ground glass).
108.47 Optical Bench, 1.5 Meters : Same as 108.46 but 1.5 meters long.
108.48 Prism Table : A brass disc 75 mm diameter mounted on a 62 mm rod giving an overall height of 62 mm.
108.49 Cross Wires : A circular blacked metal screen 75 mm dia with a 10 mm diameter aperture & cross wire of 26 swg wire. Mounted on a 6 mm brass rod giving a centre height of 80 mm approx.
108.50 Object Needle , Mounted : A pointed needle, mounted on a 6 mm brass rod, giving an overall height of 80 mm approx.
108.51 Object Screen : A circular metal screen 75 mm diameter with 10 mm central aperture covered with 1.5 mm mesh wire gauze. Mounted on a 6 mm brass rod thus giving an optical centre height of 80 mm approx.
108.52 Iris Diaphragm : A metal screen 75 mm diameter, with an adjustable iris diaphragm mounted in the centre, giving a maximum aperture of 6 mm. The disc is mounted on a 6 mm brass rod & the optical centre height is 80 mm approx.
108.53 Adjustable Slit : Circular blacked metal screen, 75 mm diameter with 12.5 mm central aperture. A screw controlled, spring loaded precision slit is mounted on one side of the disc, the adjustment drive being arranged so that the slit can not be over tightened. The slit has levelled jaws with brass, dovetail section slides, & provides a maximum slit opening of 4 mm approx. with a useful length of 10 to 12 mm. Mounted on a standard 6 mm diameter brass rod, the optical centre height is 80 mm approx.
108.54 Micrometer Slit : The micrometer slit is as above but has a heavier screw thread, 0.5 mm pitch x 6 mm diameter, carrying a drum which is divided into 50 divisions giving a reading of 0.01 mm. An index is provided with a 5 mm scale divided in 0.5 mm divisions.
108.55 Candle Holder : A cylindrical 20 mm internal diameter x 22 mm deep painted matt black is mounted coaxially upon a polished brass rod 35 x 6 mm diameter.
108.56 Ground Glass Screen : In metal frame 100 x 75 mm with a central aperture 63 mm diameter. Mounted on a 6 mm brass rod giving an optical centre height of 80 mm approx. Overall 130 mm height.
108.57 Lamp, 240 V : A 240 V 15W white B.C. Pygmy lamp in a conical lamp house 70 mm long x 65 mm diameter. Mounted on a 6 mm brass rod giving an optical centre height of 80 mm approx. Supplied complete with 1.5 mm of twin flex.
108.58 Stand for Lens Holder : Consisting of metal pillar with clamping screw, supported on a black base 100 x 50 mm with an engraved index line at one end to accept rods of 6 mm diameter as used on standard optical bench fittings.
108.59 Universal Lens Holder, Metallic : For lenses from 25 mm to 63 mm diameter, mounted on stem 6 mm diameter.
108.60 Universal Lens Holder, Spring Type : Mounted on stem 9 mm diameter to accommodate lenses & mirrors upto 75 mm diameter.
108.61 Photometer, Grease Spot (Bunsen) : Grease spot disc held between two wooden screens with 45 mm dia aperture, mounted with 2 inclined plane mirrors approx. 90 mm square.
108.62 Photometer, Grease Spot : A waxed paper screen with a wax free centre spot 16 mm wide mounted in a black metal frame 100 x 75 mm with central aperture of 51 mm. The frame is mounted on a 6 mm rod giving an optical centre height of 80 mm.
108.63 Photometer, Jolly’s : Block comprising of two pieces of polythene approx. 25 mm square, 100 mm thick, separated by tin foil, on wood stand behind aperture 12 mm diameter.
108.64 Fresnel’s Bi Prism : Optically worked, in velvet lined case
| Type | Size |
| A | 40 x 32 mm |
| B | 50 x 40 mm |
108.66 Newton’s Ring Apparatus : For measurement of wavelength of light by the reflected system. Comprising a frame 60 x 58 x 50 mm with a glass plate 56 x 47 x 3 mm mounted at an angle of 45º to reflect the light downwards on to a plano convex, 32 mm diameter x 1 m focus, which rests on a plane glass plate 38 x 38 x 3 mm on the base of the box. Complete with lens.
108.67 Newton’s Ring Microscope : This instrument is a compact instrument with full arrangements for conducting Newton’s Ring Apparatus. A standard microscope with 30x magnification is provided with a rotatable cross line & the eye piece can be focused on individual requirements. The microscope tube unit can be raised or lowered & clamped at any desired position. The focusing of microscope is through rack & pinion. The longitudinal movement of the microscope saddle for the purpose of measurement of rings is done by rotating the drum provided. The 26 mm movement can be read by the scale & divided drum to 0.001 cm. This set consists of one optical flat glass & one plano convex lens (100 mm radius) arranged inside a metal case resting over the stage of the equipment which is adjustable for the alignment of the measuring line. The condenser lens is provided in front of the reflector. In case the ring set is removed from the stage, the instrument can be used as a simple compact measuring microscope. Supplied in box.
108.68 Diffraction Gratings : Photographic replica gratings mounted on a plate glass & suitable for visual. Grading size 25 x 25 mm, on glass plate 50 x 38 mm. The grating are of :
| Type | A | B | C | D | E |
| Size (lines/mm) | 300 | 600 | 2400 | 7500 | 15000 |
108.70 Spectroscope : A simple & convenient spectroscope for taking direct wavelength readings. Five prism system. The instrument gives a dispersion of 10 legs. The slit is adjustable & a focusing adjustment provided. When the spectroscope is in operation, an illuminated screen is seen in the field of view. The divisions of this scale represent 100 A & are numbered. Scale ruling 400-700 mu.
108.71 Hand Spectroscope : Direct vision spectroscope with a fixed slit. This is useful in qualitative work, with both emission & absorption spectra where a wavelength scale is not required; with adjustable slit.
108.72 Tube, Geisssler’s : A glass tube constricted along the middle portion to concentrate the discharge glow & provided with cylindrical metal electrodes connected to 4 mm plugs mounted in moulded plastic end caps. Dimensions : 260 x 18 mm diameter. Available gases :
| A | B | C | D | E | F | G |
| Hydrogen | Nitrogen | Oxygen | Neon | Carbon Dioxide | Helium | Argon |
108.74 Student Spectrometer : The base, integral with the collimator tube support, carries the swinging telescope arm pivoted on a bearing with spring loaded end thrust plates. This type of bearing eliminates any slack which would otherwise develop with wear. The collimator & telescope tubes are one piece precision casting in light alloy, concealed helical action focusing devices are provided. The collimator slit with spring loaded jaws is of a new & robust design which ensures retention of the initial accuracy. The graduated prism table support, 180 mm diameter, is divided in degrees; the vernier, reading to 0.1, is fixed to the telescope arm. This arrangement permits easy estimation to 0.05 from the conveniently positioned vernier scale. The fully adjustable prism table 75 mm diameter is engraved with concentric rings, which facilitates correct location of a prism & has two screwed holes for the attachment of the prism & grating holder, to accommodate a prism upto 25 mm high. Large diameter clamping knob are fitted for movement control & fine adjustment is provided for the telescope. All bright parts are chromium plated with the base & tube in synthetic hammer finish. Overall dimensions 510 x 230 x 220 mm without prism.
108.75 Intermediate Spectrometer : Comprises of the following items :
a) Spectrometer : Telescope vernier reads to 1 min. of arc. A model for student use, with an optical system equivalent to that on more advanced models, thus permitting many quantitative experiments. Graduated disc 127 mm diameter, fixed to table, double ended vernier, to read to one min. of arc, attached to telescope. Both telescope & table have fine adjustment screws & release of clamping screw enables coarse adjustments to be made by hand. Telescope & collimator are fitted with 178 mm focal length, 32 mm clear aperture achromatic objectives & have rack & pinion focusing telescope fitted with 15x Ramsden eye piece & crossline graticule, collimator with adjustable slit, length 6 mm, mounting on telescope & collimator permits accurate levelling of axis & squaring of axis of rotation. The spectrometer table, marked with lines to assist positioning of prism & diffraction grating. Complete in hard wood case with following accessories: One prism clamp, one diffraction grating holder, one watchmakers’ eyeglass, one tommy bar for adjusting optical axis.b) Mercury Vapour Lamp : With holder & choke 80W & 120W.
c) Sodium Vapour Lamp : 45 Watt, 220 Volts
d) Lamphouse & Transformer : Comprising a lamphouse & transformer. The lamp gives a steady light for high intensity. Special design of transformer ensures that the lamp starts immediately as it is switched on. When mounted on the integral stand, the lamp is enclosed by a cylindrical lamp house with a circular aperture & the light centre height is adjustable from 200 mm onwards. The lamp house is open at the top to allow for ventilation & may be removed for operation on a separate stand, as required. The transformer is housed in a two part sheet steel case with ventilation louvres & has a lamp house supplying rod mounted directly onto the transformer case provide a convenient self contained assembly. A 3 core captive flying lead is provided for mains connection.
Educational Scientific Supplies Company
315-D, Mahesh Nagar, Ambala Cantt - Haryana, India. Email : info@esscoindia.com
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