Pic KIT 45

Model FERTIG made by Ph. J. Maul 
Patent 228054. August 28, 1909.  The special of the FERTIG is the indicator, which is built like an extra pendulum, and act like a self-adjusting mechanism. Placed on a slope the chart will rotate to a new resting position, but this type of indicator simply follows the chart to this new zero position. A separate leveling zero adjusting screw is not necessary with this design of letter scale. 

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