A manual dexterity test comprised of a sloping wooden tray painted black, with framing metal insert impressed with 12 identical triangular patterns, each made up of 9 depressions to take ball bearings; with two boxes (in clear archival case) of tiny steel balls. Balls made by the Hoffman Manufacturing Co. of Chelmsford, Essex. 1918-1939. Test tray looks homemade. '27' written in chalk on top side of tray. (BPS Inv. No. 0109.)