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Lead accumulator two volt battery, United States, made before 1971
Exide type DMG,lead acid accumulator battery, one of three, 2-volt s, made before 1971
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Lead acid batteries are the oldest type of rechargeable battery dating from 1860 with their invention by Gaston Planté (1834-1889). This example is shown in an experimental set up. An isolated muscle is placed on coils of wire and connected to an electrical stimulus, controlled by a switch. The muscle is also attached to the kymograph to record when the muscle contracts. When the muscle is stimulated, heat is produced and transferred to the thermocouple.The thermocouple is attached to a galvanometer to record the electric current produced.
