Spherical Conductor, 8cm Diameter Subcategory_Sound and Resonance configured to make and break

configured to make and break a circuit at the rhythm of a Morse-code transmission for telegraph-history demonstrations

supporting variable audio modulation 1Hz-1kHz plus a 250kHz square wave for speed-of-light measurement work

showing how current through an iron core builds magnetic flux in student investigations

Flame stabilizer paired with an anti-tip cast iron base on this natural gas Bunsen burner

Designed to make electric field lines visible

Spherical Conductor, 8cm Diameter Subcategory_Sound and Resonance configured to make and breakPolished 8cm brass sphere on an ebonite insulated metal base, sized to retain induced charge through demonstrations of Coulomb's law and surface charge distribution.