Early electrical equipment, historical artwork. Most of the items are different types of batteries (technically called cells). The non-battery items are: a two-way switch (bottom right), an induction coil (top right), a galvanometer (top centre), and an arc lighting device (top left). The batteries are devices from which electricity can be obtained to run an electrical device. The chemicals inside them (liquids in the case of wet batteries) react when placed in a circuit, producing electricity. The first battery was built by Volta (1800). The earliest shown here is the Daniell cell (1836, upper centre). From Cassell's Cyclopedia of Mechanics (Hasluck, 1904).