W. F. STANLEY & CO. LTD. 
i 18 
Quote Stanley’s 'A' Catalogue 
TIMBER MEASURING INSTRUMENTS 
A1940 
AI940 Hypsometer, Brandis, for measuring heights of trees, buildings, etc., con 
sisting of sighting tube and balance circle clinometer, complete in leather case, 
with tables and instructions for use. 
A1946 
AI946 “ Stanley’s ” Prism Apomecometer. A simple and convenient instrument for 
approximately measuring heights of trees, buildings, etc., This is similar to an optical 
square, but reflects at 45 degrees instead of at right angles. To use the instrument a 
sight is taken on to a spot near the foot of the tree, level with the observer’s eye, then by 
walking forward or backward the position is ascertained where the top of the tree is 
seen by reflection in the Apomecometer simultaneously with this spot on the tree. The 
height of the tree is then equal to the distance of the observer from it, plus the height 
of the sighting spot above the ground.