Keywords: Gravity cell.gif Engraving of a gravity cell from the Cyclopedia of Telegraphy and Telephony published in 1919 Grabado de una celda de gravedad o pila Daniell modificada por Pallaud hacia 1860 tomado de Cyclopedia of Telegraphy and Telephony publicada en 1919 PD-OLD Original upload log page en wikipedia Gravity_cell gif 2007-01-03 12 13 Kurzon 553×700× 68142 bytes <nowiki>Engraving of a gravity cell from the Cyclopedia of Telegraphy and Telephony published in 1919 </nowiki> History of electric batteries Gravity cells |