A Glossary of Terms for the Collector of United States Stamps

3M Corporation - private printer of modern stamps, beginning with the 1994 29¢ Eagle self-adhesive, Scott 2598.  National Label Co. actually printed this stamp for 3M.

TIPEX - see Third International Philatelic Exhibition.

Tab - the piece of paper selvage, with or without marginal marking, attached to a booklet pane.  In traditional booklets, panes were either glued by the tabs into cardboard covers, or stapled between the covers through the tab.

TAP Tagging - stamps that were Tagged After being Perforated.  This was only done to the 1966 6¢ National Park Service (Scott 1314), and 1969 6¢ Beautification of America (Scott 1365-68) stamps.

Taggant - the phosphor compound used in the tagging of stamps.

Tagging - see Phosphor Tagging.

Tagging -Type I - overall tagging where all four selvage margins on a pane of 100 stamps are only partially tagged.  The stamps are all fully tagged.  This, the first type of tagging used, appears on seven stamps.  Example: Liberty issue 4¢ Lincoln, Scott 1036a.

Tagging -Type II - overall tagging where the large margin on a pane of 100 stamps is only partially tagged.  The other three margins and all stamps are fully tagged.  Examples are many Prominent American issue stamps and a few Liberty Issues.

Tagging -Type IIA - overall tagging where all four selvage margins, as well as all stamps on a pane of 100 are fully tagged. Examples are many Prominent American issue stamps.

Tagging -Type III - tagging similar to Type IIA, but characterized by tagging gaps or bright lines resembling coil joint lines that cross the narrow axis of one row of stamps in a pane of 100.  The lines were produced by the gap where two metal tagging plates butted together.  Examples: 3¢ Statue of Liberty in the Liberty series (Scott 1035b).

Tagging - Type OP - Tagging applied by an offset press.  Example: 1966 6¢ Women's Clubs stamp,  Scott 1316.

Taker-Off-er - nickname for employees of the BEP who removed printed sheets from the flat plate press.

Teeth - the protrusions of paper on the perforated edge of a stamp that have been separated from the adjoining stamp.

Telegraph Stamps - stamps issued by private telegraph companies for use on their own telegrams.  Scott number begins with T.

Tenebrescence - see Tenebrescent.

Tenebrescent - a chemical agent that when added to stamp papers or printers ink causes them to appear darker when viewed under long wave ultra-violet light.  This is the opposite of a fluorescent agent that causes paper or inks to glow brighter under long wave ultra-violet light.  Example of tenebrescent ink: 2001 34¢ Flag over Farm, water activated gum, plate P2222.

Territorial Cover - a cover posted in what was a territory at the time of its mailing.

Test Stamp - see Dummy Stamp.

Third Bureau Issue - see Washington-Franklins.

Third Class Mail - category of mail that has evolved over the years, which has provided for the mailing of both single-piece items and, since 1928, bulk mailings.  Items mailed by Third Class have included printed mater, catalogues, seed, samples of merchandise, and advertising.  This category has been used for bulk mailings both by commercial and non-profit users.  Now known as Standard Mail.

Third International Philatelic Exhibition - one in a series of once-per-decade international stamp shows hosted in the U.S.  Held in New York City in 1936.  Souvenir sheet Scott 778 was issued in conjunction with this show.

Tied - a stamp that is connected (tied) to a cover by a cancellation or postmark.

Tobacco Sale Tax Stamp - overprinted  documentary revenue stamps issued to pay a federal tax on tobacco sales.  The Supreme Court declared the tax unconstitutional.  Scott RJ.

Toning - the undesirable discoloration of a cover or a stamp; also sometimes known as "foxing."

TOP - a marginal inscription appearing on some bicolored flat press stamps.  The purpose of the inscription was to reduce of the possibility of a sheet being inverted on its second pass through the press, and thus also to reduce the possibility of creating invert  stamps.

Toppan, Carpenter & Co. - contractor for postage stamps from 1857-61.

Toppan, Carpenter, Casilear & Co. - contractor for postage stampsfrom 1851-57.

"Track" Tagging Lines - two or more continuous horizontaltagging lines that resemble "train tracks" that are sometimes found on coils.  Under ultraviolet light the lines can be brighter tagging, or untagged lines.  The cause is wearing of the tagging ink transfer roller that was previously used for precancelling coil stamps with two lines on the Cottrell 803 press.  Track tagging is more commonly found on the Cottrell Press 1983 2¢ Locomotive coil, Scott 1897.

Trailer Permit Stamps - revenue stamps issued by the National Park Service (Dept. of the Interior).  These stamps were required to bring a house trailer into a national park or monument.  Issued in 1939.  Scott catalogue numbers begin with RVT.

Transfer Press - a special press used by a siderographer to create a plate by use of a transfer roll.

Transfer Roll - a roll of steel used in the production of a platethat prints engraved stamps. The shape of the roll is not unlike a slice of a modest sized tree branch.  Once a die has been completed, a soft, blank transfer roll is pressed into it.  In this way the design from the die is transferred to the roll in relief.  Several such designs are usually transferred onto each roll.  After being hardened, the transfer roll is used to create a plate by rocking the design into each position on the unhardened steel plate where a subject is to appear.

Transit Mark(ings) - a postal marking applied to a cover while in transit between an originating and destination post office.

*Trans-Mississippi Issue - commemorative  postage stamps issued for the Omaha Exposition of 1898.  Scott 285-293.

*Transportation Coils - an extensive series of definitive  postage stamps, which began appearing in 1981.  Scott numbers begin with 1897.

*Transports - a series of air mail stamps, all with the same design, first appearing in 1941.  Scott C25-C31.

Treasury Savings Stamp - stamp issued by the Treasury Department, redeemable in the form of War Savings Stamps or Treasury Savings Certificates.  Scott numbers begin with TS.

Treaty Rate - see Convention Rate.

Trial Color Proof - a proof, typically a die proof, printed in a test color, as part of the process of determining the color in which a stamp will be issued.

Trieste Occupation Issues - see Allied Military Government Stamps.

Triple Transfer - a plate variety in which a portion of the design is tripled, that is, it appears three times.  For further explanation see Double Transfer.

Triplex Cancel - cancel similar to a duplex, except that the year is between the dial and the killer.

Twisted Double Transfer - two impression of a double transfer that are not oriented clockwise.

Typography - see Letterpress.

U - prefix letter used by U.S. Bank Note Company in front of the plate number on its modern stamp production.

UGAI - see Ungummed As Issued.

UL - Upper left.  Refers to the upper left pane from a traditional sheet of four panes.  These initials are also used to describe plate blocks taken from the upper left corner of such sheets.

UPU - see Universal Postal Union.

UR - Upper right.  Refers to the upper right pane from a traditional sheet of four panes.  These initials are also used to describe plate blocks taken from the upper right corner of such sheets.

U.S. Automatic Vending Perforations - perforations privately applied to imperforate stamps by the U.S. Automatic Vending Machine Company for use in its vending machines.

U.S. Bank Note Company - contractor for postage stamps beginning in 1989.

USIR - a watermark found on some revenue stamps and, by error, on a printing of the $1 Woodrow Wilson stamp in the Presidential Issue (Scott 832b).  USIR is an abbreviation for United States Internal Revenue.

USPOD - see United States Post Office Department.

USPS - 1.) the watermark used on almost all watermarked postage stamps.  Some authorities believe these initials stood for United States Postage Stamp.  See Single Line Watermark and Double Line Watermark.  2.) see United States Postal Service.

USSS - see United States Stamp Society.

Ultraviolet Light - light beyond the visible spectrum.  Two different ultraviolet (UV) wave lengths are used to detect luminescence.  Long wave is used to detect fluorescent items.  Short wave is used to detect phosphor tagged items.

Uncoated Paper - Paper with a rough surface, with many jagged "hills and valleys" when looked at under magnification.  see also: Coated Paper and Prephosphored Paper.

Underfranked - an item of mail bearing insufficient postage.

Unexploded - a stamp  booklet that is intact, that is, not taken apart.

Ungummed As Issued - stamps issued without gum, as opposed to stamps from which the gum has been removed.  Farley's Follies were issued without gum.

United States Envelope Co. - manufacturer of modern stamped envelopes.

*United States Post Office Department - the branch of government that ran the Post Office prior to its reorganization in 1971.

*United States Postal Service - the government corporation formed to run the Post Office in 1971.

The United States Specialist - monthly journal of the United States Stamp Society.

United States Stamp Society - leading organization of collectors of US stamps, formerly known as the BIA (Bureau Issues Association).

Universal Postal Union - an international organization, tracing its origin to 1863, which facilitates the transmission of mail between member countries.

Universal Stamping Machine Co. - major manufacturer of cancelling machines in use from the 1900s to the 1990s.

Unlisted - a stamp or other philatelic item not recognized by a catalog publisher.

Unofficial First Day Cover - a stamp on cover  cancelled on the first day of issue, but from a city other than the one(s) in which the stamp was officially released.

*Unwatermarked - stamp or postal stationery with no watermark.