Fecha de publicación: 08/05/1919 Fuente: WIPO "pollen" 126,455. Pollen, A. H., and Landstad, H. F. May 8, 1918. Rangefinders .-A short home-base range-finder for two operators is adjusted for training and - roughly for elevation by one operator while the other effects a fine adjustment for elevation inclependently of the first operator and takes the range. The trainer sits on the seat 1 and is carried round thereon as he traverses by means of the hand-wheel 5; he adjusts for elevation roughly by means of the hand-lever 3 which actuates by means of the spindle 7 one bevel 16 of the differential 8. The range-taker sitting on seat 2 works the rangeadjusting wheel 6, and effects a fine adjustment for elevation by means of the lever 4 connected to a second bevel of the differential, the lever 4 being actuated by the hand-operated roller 18 with a pinion engaging the rack 21 on the frame to give a reduced speed. The differential actuates the range-finder through the gear 9, idle wheel 10, and circular rack 12. The lever 3 is locked to the frame 24 by a bolt 23 when inoperative.