[ ULTRA HIGH SPEED CAMERAS; ] NIGHT VIEWING APPARATUS INCORPORATING NIGHT MINIVIEWERS AND TELESCOPES; [ SMOKE DENSITY INDICATORS - NAMELY, WARNING UNITS COMPRISING PHOTOCELL ALARMS, OBSERVATION METERS, REFLECTOR AND RECORDER UNITS; ] THERMAL IMAGING APPARATUS AND CAMERAS FOR SEEING THROUGH SMOKE, LASER RANGEFINDERS, [ COINCIDENCE RANGEFINDERS, DENDOMETRIC MEASURING APPARATUS, ] PERISCOPES; [ AUTOPLOT NAVIGATION RADAR APPARATUS; NAVIGATION MANEUVERING DISPLAY UNITS; AUTOMATIC DRAFTING PROJECTOR FOR DRAFTING TABLES; DISTRESS BUOYS; FIBRE OPTIC APPARATUS, COMPRISING LIGHT GUIDES, LIGHT SOURCES, FILTER MODULES, JUNCTIONS, CONNECTORS AND SWITCH STRUCTURE COMPONENT PARTS; ] OPTICAL FILTERS AND BEAMSPLITTERS; [ COLOUR SEPARATION OPTICS FOR TV CAMERAS; ] COLOUR CORRECTION FILTERS; ATTENUATION FILTERS; FREQUENCY SELECTIVE AMPLIFIER APPARATUS FOR MEASURING LOW LEVELS OF HEAT AND LIGHT RADIATIONS; [ HEIGHT AND STAGGER GAUGES FOR RAILWAYS; BINOCULARS AND ] TELESCOPES FOR VISUAL AND INFRA RED USE; [ SMOKE DENSITY INDICATORS FOR BOILERS; AUTOMATIC MORSE CODE GENERATORS; ] LASER APPARATUS; SIGNAL PROCESSING APPARATUS COMPRISING FILTER MODULES; [ PHOTONYMOGRAPH FOR PHOTO COMPOSITION OF TYPE MATTER; SAFETY TRAFFIC SIGNS AND SIGNALS FOR CONTROL OF VEHICULAR AND PEDESTRIAN TRAFFIC BY SELECTIVE ILLUMINATION; ] FIRE CONTROL SYSTEMS COMPRISING OPTICAL TRACKING APPARATUS; WIRE HEATED WINDOWS FOR OPTICAL INSTRUMENTS SOLD AS A UNIT AND INTEGRATED OPTIC APPARATUS SOLD AS A UNIT AND STRUCTURE COMPONENT PARTS THEREFOR; ANTI-LASER PROTECTIVE GOGGLES [ AND INTEGRATED MICRODENSITOMETERS ]