The COLUMBUS BILATERAL of Ph. J. Maul seems to be described in the Deutsches Reich Patentschrift with DRP number 167192. It was granted by the Kaiserliches Patentamt and the patentee is named as AUTOMAT Aktien-Gesellschaft in Berlin. It was patented starting September 16, 1904. The patent was published January 30, 1906. Small differences can be noticed comparing the drawings of the patent with the actual letter scale: the placement of the counterweights on the letter scale is more harmonious, the plate is shaped differently and somewhat bigger, also the larger and smaller levers have geometrical differences, partly viewable here. Different designs of the COLUMBUS BILATERAL are known. The geometry of the base of the frame may differ, sometimes the weighing plate is shaped differently. The range of the letter scale shown, is 0 - 250 grams. Others range up to 500 grams.
figure 1 of the patent
