Energy Tube, teaching resource for an array of scientific concepts: open and closed circuits, conductors vs. Insulators, light waves, sound waves,currents, and energy, When a conductor touches both of the electrodes on tube, tube emits a sound and flashing red/green/blue LED lights
Hareft s Apparatus, Mounted on a wooden stand with a scale, comprises a three-limbed glass tube with rubber tubing on the centre. For comparing the densities of liquids by measuring the height of two columns of liquid produced by applying suction, Dimensions 68 x 30 x 15 cm
Highly evacuated electron tube with focusing electron gun and fluorescent screen inclined relative to the beam axis, so that the path of the beam can be seen and the effects of electric and magnetic fields can be studied.