Hartley's Rotatable Optical Disc Material_Muslin Hard-plastic 13x13-inch Worcester circuit board

Hard-plastic 13x13-inch Worcester circuit board with 12 metal poles and 4 banana terminals

this Brownlee-pattern apparatus gives a clean visual proof of the 2:1 stoichiometry of water decomposition

bundling Faraday's pail

a 125 by 65 by 18mm acrylic rectangular block with beveled edges widens the visible refraction shift in Snell's law setups

brain anatomy

Hartley's Rotatable Optical Disc Material_Muslin Hard-plastic 13x13-inch Worcester circuit board230mm disc graduated 0 360 degrees in 1 degree steps locks in any position alongside a rotatable lamp house and six magnetic acrylic elements for full ray tracing studies of reflection and refraction.