Illumination Photometer (G.B.)
Alternative term: Illumination Meter (U.S.A.) Footcandle Meter (U.S.A.)
An instrument for the measurement of illuminance.
Please note that this is the term as it stands in the original IALA Dictionary edition (1970-1989)
Celsius (previously Centigrade)
International Association of Marine Aids to Navigation and Lighthouse Authorities - AISM