Notes: "This polar planimeter by Dennert & Pape is modeled on the Amsler Type 2, but the construction - especially the two-piece arms - is very different. The model number, 590, is engraved on the planimeter, but the calibration sheet that came with it shows the model number as 1128. D&P model numbers changed to the 11xx format in 1927, so this one may have sat on a shelf for a long time. The serial number is 15202. The model 590/1128 was made for the UK/USA market, being calibrated in inches. This one was sold by Kolesch & Co. in New York. The model 1128 disappeared from the D&P catalog in 1935."
