107.1 Surface Tension Balance Searl’s : Approximately 275 mm length with cast metal bridge mounted on tripod stand adjustable for height & having a levelling knurled head screw fitted on one foot. The bridge has raised end pieces to which are screwed small metal blocks securing either end of a plated steel torsion wire. One block disc slotted to facilitate adjustment for torsion of the wire by means of screw passing through the end piece. At the centre of the wire, a small clamp is fitted carrying a light weight metal pointer with an adjustable counterpoise. From a notch near the tip of the pointer is suspended a small weight pan with a hook fitted to its underside, to hold either wire frame 80 x 25 mm or a metal clip carrying a glass microscope slide 75 x 25 x 1.5 mm. The tip of the pointer moves over a graduated vertical scale complete with set of weights 1 mgm to 1 gm.

107.2 Surface Tension Apparatus, Jaeger : Convenient for determination of relative surface tensions, or after calibration with a liquid of known surface tension for determination of that of an unknown. Complete with tap funnel, having ground glass funnel to fit the 500 ml filter flask with side arm manometer, 500 ml beaker as bath, tube 150 x 30 mm with stirrer & three jets of different sizes. All glass parts made from corning glass.

107.3 Capillary Tubes Apparatus : A 90 mm high metal frame having trough of 115 x 40 x 10 mm size. Frame having 6 holes fitted with corks. Trough which pan capillary tubes of different bore; 150 mm in length.

107.4 Kinetic Theory Model : The apparatus consists of a clear perspex tube 380 mm long & 50 mm outer diameter provided with a light, freely sliding expanded polystyrene piston & a loose fitting metal cap. The tube is mounted by means of a bayonet type fitting in a metal cap, upon a polished wood motor housing 170 x 170 x 130 mm. A low voltage DC motor is contained in the housing & is coupled to crank driven agitator. The push rod of the agitator carries a light plastic piston which oscillates in the lower end of the tube. The apparatus is supplied complete with 3 mm diameter metal spheres & four cardboard loading discs. Overall dimensions assembled 170 x 170 x 20 mm.

107.5 Smoke Cell : For demonstrating Brownian motion. Designed for use with a microscope. A short cylindrical cell, closed by a cover glass, is held vertically in an opaque channel 90 x 90 x 30 mm. Illumination is by an integral filament bulb & cylindrical glass lens. The cell enables Brownian motion to be observed for at least 15 minutes after charging the cell with smoke. Fitted with 4 mm socket terminals for connection with 12V supply. With instructions.

107.6 Air Pump : Single action Pump made of brass with oiled silk valves cylinder 200 x 32 mm. Plate 175 mm diameter with stopcock, & inlet screw fitted on teak wood polished base.

107.7 Ball & Ring Apparatus : To demonstrate thermal expansion. Comprising a brass ball 25 mm diameter, a brass ring mounted on a rod with a wooden handle, a chain is provided to hold the ball with the ring. The ball passes through the ring when cold but does not after being heated.

107.8 Bar & Gauge : A casted brass gauge with wooden handle, sliding fit over ends of bar & with hole 12.5 mm bore in both arms & a mild steel bar 110 x 12.5 mm with wooden handle.

107.9 Bar Breaking Apparatus : To show force of contraction or expansion. A heavy cast iron base with 4 uprights, on one end of which is fitted a hand nut, the other drilled with holes to carry a cast iron rod of 75 x 6 mm size bearing against narrow flats, overall size 330 x 60 x 60 mm with 12 cast iron breaking rods.

107.10 Expansion Apparatus : Comprising two iron casted stand of 180 mm height joined by two chrome plated rods, with an expansion rod, length 380 mm, fixed on one stand & resting on a Friction pointer placed at the other. With graduated scale 0-90º with 3 expansion bars of Iron, Aluminium, & Brass.

107.11 Linear Expansion Apparatus : The elongation of rod is measured by a micrometer screw. The brass tube is 500 x 25 mm C.P. With inlet & outlet tubes for steam & opening for thermometer reading to 1 x 110C. The binding posts are provided on the supports for connecting a belt, buzzer, or galvanometer for indicating the exact point of contact of the screw. Provided with three rods of Brass, Iron, & Aluminium.

107.12 Expansion Apparatus Gunther : With two cast end pieces jointed by three nickel plated rods which carry two sliding V supports for a glass jacket with inlet & outlet tubes. One end piece fitted with spherometer reading to 0.005 mm & the other with contact screw. The glass jacket enclose both a brass & a copper rod each 500 x 6 mm fitted through corks, a half turn of the jacket changing the rod in contact with the spherometer. A thermometer can be attached to either side of the rods by rubber bands. Brass terminals are fitted to the apparatus so that an electrical circuit can be made through either rod to indicate the moment of contact of centre tube & spherometer. Dimensions overall 600 x 125 x 150 mm.

107.13 Expansion of Liquids Apparatus : To show the differences in expansion of different liquids over the same temperature. Comprising five bulb tubes with plastic scales, mounted in a frame & supported in a G.I. sheet water trough 240 x 100 x 75 mm deep. The frame has clamps to secure it to the trough & two cross members having holes & upper tubules to locate the bulb tubes in bungs complete with 35 mm diameter bulbs & 150 mm scales etc.

107.14 Hypsometer Copper : For determining the upper fixed point of thermometers & boiling points at barometer pressure other than atmospheric. Comprising an upper boiling vessel with a steam jacketed inner tube. A lid with a tubule is provided which holds the thermometer under test in a bung. A side outlet draining tube & a manometric tube mounted in a tubular with rubber bung; overall size 300 x 100 mm diameter.

107.15 Compound Rod : For showing the difference in conductivity. Rod 300 x 18 mm half brass & half polished wood.

107.16 Compound Strips : For demonstrating the differential expansion of two different metals. One each brass & iron plates 350 x 35 mm riveted together from end to end with wooden handle.

107.18 Thermostat Bimetallic : Brass-invar control. For operation on gas supply, with adjustable screw valve & riffled connections for gas supply & burner. Overall length 140 mm.

107.19 Edsers Apparatus : A copper cylindrical vessel of 105 x 85 mm is fitted with 5 different rods of copper, brass, iron, aluminium, & zinc. All rods 150 x 3 mm & each having adjustable index mark at its base.

107.20 Hope’s Apparatus : For determining maximum density of water, made of G.I. sheet cylinder 50 mm diameter x 300 mm height mounted on a base having two tubulators for thermometers, with a gallery of 60 mm x 150 mm for placing mixture of ice & salt. The respective temperatures of water at the top & bottom of the inner cylindrical vessel are measured over a period as the water cools. Complete with bungs & thermometers.

107.21 Charle’s Law Apparatus : With a glass U tube with a bulb & tap at the upper end of one limb, other limb open. From the bottom of the U is an outlet tube which passes through a bung & terminates into a tap. The bulb has a capacity of 7 cm³ & the stem beneath is graduated 3 x 0.1 cm³ allowing for expansion over a range of 100ºC. The apparatus can be supported by a single clamp & only 20 cm³ of mercury is required.

107.22 Constant Volume Air Thermometer : Consists of a polished teakwood stand approx. 750 mm high fitted with a wooden scale reading from 0 to 60 cm x 1 mm & supporting an adjustable mercury reservoir by a metal rod. A detachable air thermometer bulb about 70 mm diameter connected via three way stop cock to mercury tube with zero index fused inside its upper end. A metal vessel surrounding the bulb supported by detachable metal shelf mounted on insulated asbestos screen. Mounted on a teakwood stand with a deep tray which serves to catch any mercury spilled accidentally from the reservoir. Supplied complete with 1 meter of rubber pressure tubing 10 mm outer diameter & 5 mm bore for connecting the reservoir to the bulb.

107.23 Iron Flask for Freezing : For demonstrating the expansion of water on freezing. A cast iron bottle 100 x 25 mm approx. which can be sealed by means of a well fitting screwed in iron plug.

107.24 Regnault’s Hygrometer Simple : For determining the dew point. Comprises a glass tube 150 x 25 mm with polished silver thimble closed bottom of the tube & the upper end by a rubber bung. The bung has two glass air tubes with right angled bends. One tube ending just below the bung, the other reaching nearly to the bottom of the thimble & a hole for thermometer which reads 10 to 50ºC x 0.5ºC.

107.25 Latent Heat of Steam Apparatus : Comprises a thick brass calorimeter, a bung with steam inlet & outlet glass tubes, a felt cover, complete with 2 litres tin plate boiler with bung to take the steam tube which connects to the calorimeter.

107.26 Calorimeters Copper/ Aluminium : One piece spinning with parallel sides & rolled rim. Type A) B) Size 75 x 50 mm 100 x 75 mm Available in both Copper & Aluminium.

107.27 Calorimeter Set : A complete set comprising the following : 1 copper calorimeter 75 x 50 mm 1 wooden outer box with felt lining 100 x 75 mm approx. 1 sliding wooden cover for outer box 1 copper stirrer with loop to fit inside the copper calorimeter 1 thermometer holder made of brass, removable

107.28 Calorimeter Set Copper : Consisting of spun copper cylinder contained within a large 75 mm diameter x 100 mm aluminium outer vessel with 10 mm of insulating material between. Supplied with wooden cover for outer vessel with bung for mounting thermometer support clip. Dimensions : 110 mm x 200 mm overall.

107.29 Joule’s Calorimeter : For determining the specific heat capacity of liquid by electrical method. Consisting of a nickel plated copper vessel 75 x 50 mm size with outer vessel of teak wood fitted with bakelite top with hole for thermometer. The terminals connected to a coil of wire (for current up to 3 amps.) are fitted, complete with stirrer & outer teakwood vessel.

107.30 Metal Block Calorimeters : For experimental determination of the specific heat capacity of different metals. Cylindrical metal blocks of mass 1 kg; adjusted to accuracy of ±2%. Each block drilled with two holes. A large central hole 12.5 mm diameter for a special immersion heater & a smaller hole, 7.5 mm diameter for a thermometer.

107.31 Cylinders Set Equal in Size : A set of 6 metal cylinders 40 x 10 mm of copper, brass, iron, zinc, lead, & aluminium packed in card box. Each drilled for suspension.

107.32 Cylinders Set Equal in Mass : A set of 6 metal cylinders of copper, brass, iron, zinc, lead, & aluminium of 100 gms each (±10%) & each drilled for suspension.

107.33 Steam Boiler with Water Gauge : A copper vessel having a cylindrical body & a conical top with a short neck for a bung. Fitted with a finger loop handle, steam outlet tube riffled for rubber tubing, & a glass water gauge tube. Type A) B) Capacity 1 litre 2 litres

107.34 Steam Heater : Special design made from thick copper sheet 175 x 100 mm having filling tube with ebonite collar, steam vent & vertical tube terminating in chute passing through the side of vessel. A brass tube sliding fits into the central tube to carry thermometer. Lower end cut an angle to seal the chute.

107.35 Steam Trap : All glass, overall length 160 mm.

107.36 Thermal Conductivity Kit : A set of 5 different material rods of size 250 x 3 mm of copper, brass, aluminium, iron, & borosilicate glass. Set consists of 8 rods each packed in card box.

107.37 Ingen Hausz Apparatus : Consists of a metal tank 150 x 90 x 100 mm has six apertures on one side through which 100 x 3 mm metal rods of copper, brass, aluminium, iron, zinc & lead pass. The outer end of each rod has a cavity. When the low melting point paraffin wax is placed in the cavity, the different metals melt the paraffin at different rates.

107.38 Conductivity Apparatus : Consisting of 4 metal strips of copper, brass, aluminium & iron of 100 x 15 mm having small cups at outer ends for holding phosphorous & screwed on a wooden ring 125 mm outer diameter meeting in the centre.

107.39 Searle’s Thermal Conductivity Apparatus : Consists of a cylindrical copper rod about 300 mm long & 25 mm diameter with its one end surrounded by a steam jacket for heating it from a boiler & the other end is kept cool by a system of water flowing through a spiral tube soldered to that end. Through two sockets, two thermometers are inserted in the rods for finding the temperature at two points. Two more thermometers are inserted in the other end which is kept cool by the stream of water. Through this apparatus, the difference of temperature between the inflowing & outflowing water is determined. Fitted in teak wood case, packed with felt with removable front; with thermometers.

107.40 Lee’s Thermal Conductivity Apparatus : For determining the relative conductivity of bad conductor material. Consists of a cylindrical slab of brass 115 mm in diameter & 12 mm thick drilled to take thermometer. On this rests a 50 mm deep steam chest of the same diameter with inlet & outlet tubes for steam. The apparatus is suspended by strings attached to the lower end of the cylinder with thermometer. On retort stand with rectangular base 200x125 mm & rod 600 mm long. Complete with one each disc specimens, glass & plastic 3 mm & 1.5 mm thick respectively. For determining the conductivity of liquids.

107.41 Lee’s Disc Apparatus : For measuring thermal conductivity of poor conductors. The apparatus is capable of a high degree of accuracy & consists of three cylindrical blocks of aluminium 50 mm diameter x 12.5 mm thick, drilled radially to take thermometers. Between the first 7 second block is inserted a small 4 to 6 V electric heater, sandwiched between mica sheets of known resistance. The test specimen, in the form of a thin disc is inserted between the second & third blocks & the whole is clamped together by an insulating clamp. The assembly is supported upon a sheet metal stand 118 x 70 x 90 mm high notched to locate the clamp rods. Supplied complete with stand.

107.42 Continuous Flow Calorimeter : For determining the specific heat of water or similar liquid. Consists of a glass tube 100 mm long with heating element (electric wire). Two screw terminals are provided at the ends of the tube for electric supply. The horizontal tube is connected by means of rubber bungs to the inlet & outlet system. Each having a vertical expansion to accommodate the thermometer. A stream of water is made to flow through the glass tube & heated by the spiral by passing electric current. With the help of an adjustable constant boil tank, the rate of flow is kept constant. The rise in temperature of water is measured by two thermometers. The whole apparatus is mounted on a polished wooden base approx. 625 x 130 mm in size. Supplied with thermometer.

107.43 Constant Level Tank : Comprising a brass cylinder 100 x 75 mm diameter with 3 tubes for water inlet, outlet, & overflow with a bosshead & stand.

107.44 Convection Tube : To show convection of heat in water; comprising a rectangular glass tube 200 x 350 mm of 20 mm glass tubing. The short side having a funnel for filling.

107.45 Ventilation Apparatus : Comprising a metal box 250 x 75 x 75 mm with a sliding glass front & two detachable glass chimneys mounted in clips. Candle holders are provided under each chimney.

107.46 Leslie’s Cube : For showing that different surfaces radiate heat at different rate. Cube made of tin plate120 mm side having a top opening. The vertical faces of the box are blackened dull, blackened bright, white & bright tin.

107.47 Parabolic Reflector : For reflecting & focusing radiant heat. Comprising two 250 mm diameter highly polished metal reflectors mounted with a screw clamp on a 12.5 mm thick rod 500 mm long with tripod base.

107.48 Radiation Kit : A class kit sufficient for thirty two students. The kit contains : Four 230-250 V radiant heat source 1 copper plate radiant 230 x 230 x 5 mm with a 12.5 mm steel rod handle protruding approx. 205 mm. 4 heat resistant screens 300 x 300 x 3 mm with a 25 mm hole near the centre. 4 glass plates 230 x 3 mm

107.49 Card Board Tube : For rough determination of joule’s mechanical equivalent of heat. A stout card board tube 750 mm long & 50 mm diameter fitted with 2 corks.

107.50 Ether Thermoscope : For determining thermal radiation with bulb 30 mm diameter approx. One bulb painted matt black. Partially evacuated.

107.51 Crooke’s Radiometer Single : Evacuated glass bulb of approx. 70 mm diameter having fine pivot at its centre which supports four light weight vane of mica 10 mm square approx. & blackened on one surface. Mounted on a bakelite stand. When exposed to sunlight or bright lamp. The rotor rotates rapidly.

107.52 Crooke’s Radiometer Double : Construction is same as in 107.50 but having two bulbs with two sets of vane; when exposed to sunlight, the vanes rotate in opposite directions.

107.53 Thermocouple Simple : To show production of a thermostatic EMF. To wires of copper constant 300 mm long joined together at one end.

107.54 Thermopile Copper Iron : Four each of copper & iron wires 125 mm long joined together from 7 points; four on one side & three on the other. With brass connections on the outer wires.

107.55 Thermocouple Bismuth & Antimony : One bismuth & one antimony base 60 x 5 x 2 mm joined in V form at one end & mounted on a wooden board 80 x 70 mm with copper connecting wires.

107.56 Thermopile : Consists of 24 pairs of bismuth & antimony bars connected in series & arranged in the form of a rectangular pile with the junctions equally divided between the two ends. The pile is mounted in a cylindrical housing provided with 4 mm socket terminals mounted with a rod on a heavy metal base. A removable brass nickelled funnel is provided to fit over the ends of the pile.

107.57 Searle’s Mechanical Heat : Sturdy construction with hand rotating device in vertical plane. In this experiment, work is converted into heat caused by the friction between two well fitting gun metal cones. The inner cone is fitted with a known quantity of water & thermometer is held stationary (while the wheel is in motion) with the help of counter torque applied to the bigger round wooden disc by cord & slotted weights. A counter is fitted for recording the number of revolutions. A slot is provided in the metallic frame to adjust the belt.

107.58 Constant Pressure Air Thermometer : Consists of a polished teakwood stand approx. 750 mm high. A reservoir bulb sliding on vertical clamping rod. A detachable air thermometer bulb 70 mm dia connected via 3 way stop cock to U tube with wide bore left hand limb graduated 0.60 x 0.2 ml & sliding indicator on right hand limb to obtain level. Base of U tube connected by rubber tubing to reservoir bulb. A metal vessel surrounding the bulb supported by a detachable metal shelf mounted on insulated asbestos screen mounted on the stand with a deep tray, supplied complete with 1 meter of rubber pressure tubing for connecting the reservoir to the tube.

107.59 Dulong & Petit Apparatus : For determination of coefficient of absolute expansion of mercury. Modified form. Consists of columns surrounded by a glass jacket approx. 460 mm long & 25 mm diameter closed by rubber bungs & fitted with inlet & outlet tubes for steam & cold water respectively. The lower ends of the tubes are bent & are connected horizontally. The upper open ends of the vertical limbs are bent so as to be placed side by side against a silvered glass scale 0-12 cm figured every 2 cm. The whole apparatus is mounted on a wooden stand by means of spring clips. All the glass parts are easily removable. Overall height about 750 mm.

107.60 Flywheel Unit : Comprising an iron flywheel 115 mm diameter, mass 1.2 kg, mounted in cast brackets with nylon bearings. The shaft has an aluminium V pulley 44 mm diameter for driving with the spring belt. Dimensions of laminated wooden base 155 x 105 mm.

107.61 Friction Calorimeter Unit : Comprising a brass cylinder, internal size 27 x 16 mm diameter, with an integral V pulley in the base of the cylinder & a 6 mm wide steel shaft which fits into a bearing block. A vertical pillar carries the cork lined friction arms & thermometer support. Dimensions of laminated wooden base 155 x 105 mm.