Archive of Collections

Details and Image

TypeModel No.MakerCountryConstruction
DateScale LengthArea of Use
E.O. Richter System Pregèl Hatchet Planimeter
E. O. Richter
Brass and German Silver
ca. 1910
General area measurement

Notes: "The System Pregèl is perhaps the most interesting variation on the hatchet planimeter. Instead of a knive edge, it has knife-edged wheels that roll over the paper, without cutting it. There is a push button to make a mark in the paper at the start and end of the trace, and the effective length of the tracing arm is adjustable. It even has a round ball that slides on the paper, keeping the tracing point from scraping across the paper. While all that makes for a spectacular hatchet planimeter, it misses the point that the hatchet planimeter was supposed to be much cheaper than a polar planimeter, while giving up some accuracy. This hatchet planimeter has more parts - machined parts! - than some polar planimeters. This one is serial number 660."

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