Portal:Philately/Selected article archive/3
Letter sheets are items of postal stationery issued by a postal authority. A letter sheet is a piece of paper that can be folded, usually sealed, most often with sealing wax in the 18th and 19th century, and mailed without the use of an envelope that only became popular in the late 19th century.
The first postal stationery item issued by a government is thought to be the coat of arms of Venice on a 1608 lettersheet. Part of Rowland Hill's postal reforms in the United Kingdom were the introduction of prepaid lettersheets and envelopes in 1840 designed by the artist William Mulready, whose name is always associated with these lettersheets and envelopes. Aerograms are a mid-20th century development of the letter sheet.