Periscope At hairdresser's State-money box Kaleidoscope
A mirror or a window? A glance in the distance Universal mirrors Mirage
Three-dimensional goat Bubble sphere Penguins Fibre-optic cable
Entomologist's microscope Telescope A magic eye Battery stall
Colourful tops Sunglases Svarowski's sphere Counterfeit banknotes
Chromatic glasses CD spectrometer Soap bubbles Invisible beams