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Fig 1: Rotating catoptric apparatus with metal reflectors

Fig 2: Fountain-type oil lamp with catoptric reflector

Fig 3: Argand lamp section

Fig 4: Fresnel's polyzonal dioptric lens

Fig 5: Cross-section of dioptric lenses

Fig 6: Brewster’s segment of a dioptric lens

Fig 7: Brewster’s arrangement of lenses and mirrors

Fig 8: Front and side-view of catadioptric fixed first-order lens

Fig 9: Side elevation and partial cross-section of a first-order revolving lens

Fig 10: Diagram to explain the ‘dip’ of a lighthouse beam

Fig 11: James Chance's Dioptric Mirror

Fig 12a, b and c: Gustaf Dalén’s inventions for lighthouses lit by acetylene gas