Imperial diptych offerings to the emperor. However, the fact that the Barberini ivory was almost certainly not a diptych, but some kind of imperial icon without a second panel is a serious argument against the existence of the imperial diptych type. The two panels representing the empress Ariadne, in the Bargello in Florence and the Kunsthistorisches Museum in Vienna, also belong to the hypothesied imperial diptych type. They are the only central panels of such a diptych (other than the Barberini ivory) to survive, since all other fragments of such diptychs are from side panels. Imperial diptych In Late Antiquity, an imperial
Imperial Gift Army). The Imperial Gift enabled the formation of the Royal Australian Air Force on 31 March 1921. An Air Board, answering to the Minister for Defence, would administer the new service. Imperial Gift aircraft were shipped to Australia in 1919, assembled upon delivery in 1920 and served for up to 10 years. The Airco/de Haviland DH-9a (A1-17/F2779) was the longest serving Imperial Gift aircraft, being written off on 4 February 1930. The only original surviving Imperial Gift aircraft in Australia are an Avro 504K (A3-4/H2174), stored at the Treloar Technology Centre (Canberra) and an S.E.5a (A2-4/C1916), in the collection of