143. Wynne's Infallible Print Meter, c. 1897

Signed: 'WYNNE'S / INFALLIBLE / PRINT METER' with bishop's mitre trademark.

Metal box fronted by a sheet of optical glass behind which is a plate perforated with a series of holes so that each one admits 10% less light than the previous one. The number and strength of the figures printed with a standard exposure indicates the length of exposure required for carbon printing.

Height 65 mm, width 50 mm, depth 15 mm.
Inventory no. 86,540.