Whispering-gallery wave known as surface plasmons has been demonstrated in the form of whispering-gallery waves, and likewise for exciton-polaritons in semiconductors. Galleries simultaneously containing both acoustic and optical whispering-gallery waves have also been made, exhibiting very strong mode coupling and coherent effects. Hybrid solid-fluid-optical whispering-gallery structures have been observed as well. Whispering-gallery wave Whispering-gallery waves, or whispering-gallery modes, are a type of wave that can travel around a concave surface. Originally discovered for sound waves in the whispering gallery of St Paul’s Cathedral, they can exist for light and for other waves, with important applications in nondestructive testing, lasing, cooling and sensing,
Scottish National Portrait Gallery but the government in London refused to fund the venture. Eventually John Ritchie Findlay stepped in and paid for the entire building, costing £50,000. The museum was established in 1882, before its new building was completed. The London National Portrait Gallery was the first such separate museum in the world, however it did not move into its current purpose-built building until 1896, making the Edinburgh gallery the first in the world to be specially built as a portrait gallery. Special national portrait galleries remain a distinct Anglophone speciality, with the other more recent examples in Washington DC (1968), Canberra, Australia