3 dendrometers for measuring the height of trees. 19th-20th c 1. Franck dendrometer. Copper, plated, 11 x 9 x 8 cm. - 2. 13,6 cm copper. - 3. altometer Franck. Copper, 12,5 cm (all without plumb). Joined: Unidentified measuring instrument. Metal, 15 x 10,5 cm (4 pcs)

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