BOXED RANGE FINDER COTTON TYPE MKII made by E.R. WATTS AND SON LTD. , LONDON No. 1194. Circa 1930-1945.
Prismatic range-finder Cotton Type MK II. Naval Rangefinder with a vertical turned wooden handle, and an arrangement of optical lenses. Three reversible brass inserts calibrated on both sides in yards, correspond to various base heights, (20 and 25 feet, 30 and 35 feet and 40 and 50 feet). They are fitted along the axis of the instrument. When the scale for the appropriate base height is selected and inserted, the carriage can be slid for coincidence and the distance read at the index mark on the sliding carriage. Inscribed "Rangefinder Cotton Type Mk II" Calibrated scale up to 5000 yds (50 ft), 5000 yds (35 ft), 4000 yds (25 ft) made by E. R. Watts & Son. The box instrument holders are partly lined in green felt and two brass latch hooks hold the box closed. It measures approximately 11" (28cm) in width, 3.5"(8.5cm) in depth and just over 2" (5.5cm) high. The Rangefinder and the box are in good condition as shown.
From the Edward L. Greenwood Maritime Museum Collection