Transparent acrylic plastic ripple tank, supported in a sturdy plastic frame which has recesses to hold four legs with leveling feet. The tank edges are shaped to minimise undesired reflections. Tank has a drain hole closed by a rubber stopper. With two light alloy uprights to carry a horizontal rippler support rod which is adjustable for height. The ripple assembly, elastically suspended from the support rod, consists of a 4 – 6 V DC motor mounted on a wooden beam. The motor has an eccentric weight which causes the beam to oscillate. Two point sources are provided by two plastic spheres, each mounted on a right angle rod. A metal rod is fixed centrally into a socket in one short side of the frame to afford support to the illuminant. Overall size of the tank 580 x 500 x 80 mm, window area 370 x 280 mm, height of tank above bench level (with legs attached) approx. 375 mm. Complete with following accessories :- 1. Two straight obstacles of aluminium alloy length 130 mm 2. One straight obstacle length 40 mm. 3. One curved reflector radius 200 mm. 4. One trapezoidal plastic plate for refraction. 5. One wood hand wave roller. 6. One water dropper. 7. One pkt. rubber bands. 8. One foam plastic sponge. 9.One illuminant with a 12 V, 24 W lamp mounted in a lamp house and provided with a long supporting rod which can be attached to a retort stand. With instructions.

Set of 20 Igeneous metamorphic and sedimentry rocks in wooden box with glass top

A collection of different rocks and minerals, in wooden box, with containing 50 specimens. Each specimen is labelled.

A comprehensive collection of igneous , metamorphic and sedimentary rocks, in wooden box, with partitioned tray containing 50 specimens, each nominally numbered and enclosed in a transparent plastics bag. Specimens may be removed from bags for detailed examination. Each specimen is labelled also on the inside of the box lid, indicating the geological name.