Trough battery spaces between the plates (the troughs) were filled with dilute sulfuric acid. So long as the box was not knocked about, there was no risk of electrolyte spillage. Trough battery The trough battery was a variant of Alessandro Volta's Voltaic Pile and was invented by William Cruickshank c. 1800. Volta's battery consisted of brine-soaked pieces of cloth sandwiched between zinc and copper discs, piled in a stack. This resulted in electrolyte leakage as the weight of the discs squeezed the electrolyte out of the cloth. Cruickshank solved this problem by laying the battery on its side in a rectangular box.
NZR RM class (Edison battery-electric) NZR RM class (Edison battery-electric) The NZR RM class Edison battery-electric railcar was a popular and successful railcar that ran in Canterbury, New Zealand for eight years. The prototype, RM 6, was arguably the first successful railcar in New Zealand, but the type was not developed into a class. The railcar had a wheel arrangement of Bo-Bo under the UIC classification system, weighed , had driving controls at each end, and with an engine output of , it travelled comfortably at . In appearance, it looked like a cross between a regular railway passenger carriage and a tram; side-on, it