Pair, Carte de visite, a type of small photograph which was patented in 1854, each photograph was the size of a visiting card, and such photograph cards were commonly traded among friends and visitors in the 1860s, Visitformat, Carte de Visite, photograph fixed on cardboard in the format from approx. 6 x 9 cm, from approx. 1860 the Carte de Visite became very popular and made a major contribution to the spread of photography