ZES 390. Ripple Tank :

A wooden framed tray with sloping position in side to minimise unwanted reflection from the sided of the tank with perspex plastic base and 4 detachable legs. Overall size of tray 600 x 520 x 55mm deep. Support rod with G clamps are provided for using to carry waves generating system. Four metal barriers (reflectors) consisting of a pair of straight barrier 150 x 25mm chord barrier of 215mm chord length x 25mm high and a short, straight barrier.

Ripple are produced by a small 1.5 to 4.5V DC electric motor mounted on a 330mm wooden bar having a row of holes to mount spherical dipper. Completer with 12V illuminator with clamp.

ZES 391. Power Supply Unit :

For use with the ripple tank. It has continuously variable d.c.output so that the speed of the motor and the frequency of the ripples may be varied.

ZES 392. Set of Extra Accessories :

Water dropper, Woodenrod 230 x 25 mm diameter, rubber tubing, 600 x 6mm bore, glass plate 300 x 202 x 4 mm, Hoffman Clip, sponge for illuminant.

ZES 393. Hand Stroboscope :

Aslotted hardboard disc with finger hole, is pivoted on a bearing mounted which also acts as a convenient handle. The disc has twelve radial slots 50 x 3mm extending to its edge.

Diameter of disc 250mm.

ZES 394. Student Sonometer :

Comprising a wooden board 690 x 90mm mounted on four feet, at one end of the box are two 5kg x 100gms spring balances with hooks and at the other end are two wrest pins with 3 Bridges out of which one is large to span both wires and the other two are small for the individual wires. Complete with steel wires and pins.

ZES 395. Sonometer :

Comprising a hollow wooden box 1140 x 125 x 100mm length x width x height with 2 metre, rules, 1 metre long divided in mm. Two wires of brass and steel attached to fixed bridge and tensioned by fine adjustment pegs, two movable Bridges, Pulley and fixed screw to enable a third wire to be fixed for tensioning by masses. Complete with 2 Bridges.

ZES 396. Tuning Forks Set Blue Steel :

Set of 8 of blue steel, plain shank, one each of C(256) D.E.F.G.A.B.C.(512) in velvet lined box.

ZES 397. Tuning Forks Set of 13 :

Chrome plated, with frequency marked, a set of 13, of different frequency from 256 C to 512 C, packed in velvet lined box.

ZES 398. Tuning Forks Set of 13 :

Same as above made of aluminium alloy rustless.

ZES 399. Tuning Forks on Resonance Boxes :

Set of three tuning forks, two C 256 and one C 512 mounted on resonance boxes with brass plates drilled and threaded to take the threaded shanks of the forks. The length of each box is carefully adjusted to suit the frequency of the fork and is mounted on cork feet.

ZES 400. Set of Four Forks on Box :

For demonstrating the formation of a basic major chord. Comprises four forks mounted on a comman box and having frequencies of C 256Hz. E 320Hz, G 384Hz and C 512Hz. When sounding together, therefore, the forks produce the chord of C major.

Dimensions of resonance box : 285 x 115 x 63mm LxWxH.

ZES 401. Hammer for Tuning Fork :

Made of wood with rubber head.

ZES 402. Stethoscope :

Ahigh quality, professional pattern model for human heart and chest sounds with combination chest-piece giving a choice of bell or diaphragm. Complete with spare diaphragm.

ZES 403. Electrical Tuning Fork :

On sturdy streamlined base with provision for horizontal or vertical use. Fork is manufactured from selected steel. Prong is 10 x 25 x 300mm. Accurate frequency adjustment, chrome plated, vibration rate 60 per second. Electromagnet can work on 6 volts. The amplitude of vibration can vary by sliding the electomagnet inside prongs. Complete with style, mirror and counterpoise.

ZES 405. Meldes Apparatus :

To demonstrate stationary waves by means of stretched strings. Consists of an electrically maintained tuning fork, bench clamp pulley, scale pan and metre scale.

ZES 406. Organ Pipe :

Varnished wood with glass front and membrane suspended on cord for loading with sand to show positions of nodes and antinodes.Overall length 760mm.

ZES 407. Organ Pipe Sliding :

With graduated sliding piston. The organ pipe is of a square section of polished wood and fitted with a tapered mouthpiece.

The slider is also square in section. 32 x 32 mm of wood and with a knob at the end for easy control. The slider has a scribed and lettered line for each note which may be aligned with the end of the pipe to give a diatonic scale from c 256 to c 512. Overall dimensions closed 540 x 50 x 50mm.

Overall dimensions : 520 x 50 x 50mm.

ZES 409. Whirling Table :

Overall height 430mm for use in vertical or horizontal position, fitted with handwheel and wire helix belt drive to pulley and with the adapter supplied all accept colour disc.

ZES 410. Savarts Toothed Wheels :

A set of four toothed wheels 75mm dia on a common spindle. The wheels have 40,50,60 and 80 teeth respectively giving intervals of 1:5/4:3/2:2 and thus forming the basic major chord.

ZES 411. Resonance Apparatus Glass :

A glass tube 340 x 25mm length x O.D. Mounted on retort stand with clamp and boss head, with 500ml glass bulb, connecting tubing and spring clip supported on rubber covered split iron ring.

ZES 412. Resonance Apparatus :

Consists of a resonance tube brass N.P.100cm. reservoir brass N.P.250ml and metre scale both side mm which are mounted on wooden block which is having sliding and clamping arrangement on board. The board is mounted vertically on heavy metal base synthetic hammer finish with levelling screws. Complete with rubber tubing.

ZES 413. Resonance Apparatus, Simple Form :

For measuring the resonant length of an air column driven by a tuning fork. Comprises a brass tube 290 x 25mm dia fixed to a base 150 x 150 x 20mm with a sliding inner tube 300mm long which allows the length of the air column to be varied from 350 to 530mm.

ZES 414. Resonance Tubes :

Comprising two glass tubes, one 300 x 32mm dia the other 300 x 25mm dia. The smaller tube slides within the other in foam plastic collars, allowing the air column length to be varied from 300 to 530mm.

ZES 415. Kundts Tube Apparatus :

Consisting of a glass tube heavy walled 1350 x 32mm length x I.D with cork bung, short and long Ebonite Rod, cork pistons, mounted on a polished wooden board 1520 x 125 x 22mm L x W x D with spring clamps. The long Ebonite Piston supported by wood clamp secured with wing nuts.

ZES 416. Crovas Disc :

For showing progressive waves. Printed on card, 250mm diameter, with printed slit and instructions.

ZES 417. Cheshires Disc :

For showing standing waves, printed on card, 250mm diameter, with printed slit and instructions.

ZES 418. Dog Whistle :

A mouth blown tunable high frequency whistle, range from just audible in inaudible. Upper range can be detected by microphone and shown on an oscilloscope and is within the audible range of a dog.

ZES 419. Falling Plate Apparatus :