Bell in Vacuum, Glass, DC Subcategory_Lab Burner Accessories Carbon anode-and-cathode pair pre-fitted in

Carbon anode-and-cathode pair pre-fitted in a rubber bung

Half life-size circulatory system board traces arterial and venous pathways from heart to peripheral capillaries with numbered

and a 60mm scale

Air-cooled rheostat with extended-tube ventilation

Larger-spark 100mm induction coil from a 6-12V DC input with adjustable vibrator and base-mounted suppression capacitors

Bell in Vacuum, Glass, DC Subcategory_Lab Burner Accessories Carbon anode-and-cathode pair pre-fitted inBell in vacuum jar with a 4 6V electric bell suspended on rubber cord inside a 22 by 15cm glass chamber, illustrating that sound cannot travel without air.