Flaman Speed Indicator and Recorder
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The Flaman Speed Indicator and Recorder was a device patented in 1901 by Nicolas Charles Eugène Flaman of France for indicating the current speed of a vehicle (for example a railway locomotive) and recording it on a paper tape that could be unrolled and examined at the end of a run to provide evidence of the speeds attained on the journey.[1]
The paper tape recording was driven directly by the wheels of the locomotive, with the paper spool moving at a fixed rate per kilometre travelled. Three graphs were recorded, the first being time elapsed (with the trace moving vertically if the train was stationary), the second being a speed curve.[2] and the third recording the driver's attentiveness to signals ("Vigilance") by marking one tick above a line when the driver depressed a button, and another below the line when the engine went over the signal ramp.