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This paper discusses the connection of Charles Wheatstone with the bridge circuit. It investigates whether Wheatstone invented the bridge or not. Upon the development of the electric telegraph by Samuel F.B. Morse in 1832, the need to measure resistance accurately arose. Because telegraph lines were many miles in length, it was necessary to know the resistance of a specimen of the line wire very accurately so that the total line resistance could be predicted with accuracy. Knowing the resistance of different wire diameters and different metals were essential for the success of the electric telegraph. Wheatstone's contribution to the success of the electric telegraph was the accurate measurement of the resistance of wires. He first invented a variable resistance (rheostat) that consisted of two identical parallel-grooved cylinders that could be made to rotate synchronously in opposite directions. Wheatstone described his measuring circuit in the Philosophical Transactions of the Royal Society in 1843. He called it the differential resistance measurer. Wheatstone's differential resistance measurer is a voltage comparator.