See Privilege Stamps.

Stamps printed in "singly fugitive" inks afford a protection against the removal of postmarks. "Doubly fugitive" inks afford an extra

In early times Court or Government officials and other privileged persons were allowed to send correspondence free, under cover of

A genuine stamp that has been tampered with fraudulently to increase its supposed value to collectors. A normal stamp cunningly

An imitation, akin to a forgery, but sometimes marketed with an overprint denoting its character, e.g. Facsimile, Falsch, or with

The denomination or value stated in words or figures on a stamp.

The front or design side of a stamp.

An envelope, letter, card, pigeongram, etc., bearing evidence of having been transported by air.

A damage to a printing plate or stone may cause a reproduction of the flaw in the printed sheet. Such

A collection formed on broad lines, embracing a wide area or group of countries, without specialisation.

In U.S. stamps identical in design, colour and denomination have been printed on flat-bed and on rotary presses; they are

Fiscal and fiscally used stamps are not generally acceptable to collectors of postage stamps. There are collectors in most countries

A stamp used for revenue purposes other than postage. F.C. is a commonly used contraction to denote that a stamp

In aero-philately special attention is given to cards and covers carried on the first flights, whether experimental pioneer efforts or