For measurement of heights and setting of slopes and falls. Polished brass arc 74 mm. diameter divided 90-0-90°C with vernier scale reading to 10 min. of arc operated by knurled knob which also carries the spirit level. Gradient scale 0-10 x 1. With a magnifier lens for easy viewing of scale. Sighting tube of square-section brass 125 mm. long.

Catalogue No. PM-731