A Glossary of Terms for the Collector of United States Stamps

D - prefix letter used by Dittler Brothers, Inc. in front of the plate number on its modern stamp production.

"D" Press - webfed press with both offset and intaglio capacities in use at BEP 1984-1996.

DPO - see Discontinued Post Office

Dated Precancel - a precancel stamp marked by the user with the month and year of use.

Dead Letter Office - unit of the post office that received undeliverable mail that did not have a return address.  The Dead Letter Office attempted to return the letter to the sender.

Decorative Banner - the illustrated margin on the top of some modern commemorative  panes.  It has no postal value.  Example: 1996 Summer Olympics, Scott 3068.

*Definitive - postage stamp intended for routine postal use, issued for an indefinite period of time in indefinite quantities.  Also called ordinary stamps.

Delivery Confirmation - service for a fee that provides the sender with the date and time of delivery.

Demonetized Stamp - a stamp that is no longer valid for postage.  The stamps issued prior to the Civil War have been demonetized.  Most pre-1979 postal cards have been effectively demonetized because they do not meet current minimum size requirements.  Likewise Special Delivery stamps and Newspaper and Periodical stamps have been effectively demonetized.

Denominated Postal Cards - postal cards printed by vending machines in selected locations during the early 1990s.  Scott CVUX.

Denomination - the face value of a stamp, as printed on the stamp, normally in numerals.  Compare: Nondenominated Stamps.

Departmental Stamp - see Official Stamps.

Design - the image on a stamp.

Designer - the person who creates the artwork that is the basis for a stamp.  Most stamps were once designed by employees of the BEP (e.g. Smith, Huston, Meissner, McCloskey and Chickering).  More recently the Postal Service has relied on non-government employees for designs.

Diagonal Half - a fractional usage - a stamp bisected diagonally.

Dial - circular postmarking  die, used to impress a postmark on an envelope, generally containing the following information: city and state of mailing, as well as the date and time the postmark was applied.

Die - 1.) the piece of steel on which a design is engraved.  A die has the stamp image engraved in reverse (mirror-image).  The making of the die is the first step in the production of engraved stamps.  The die can be said to be the "parent" of the completed stamps.  2.) the printing surface, found in a cancelling machine, from which a cancellation and postmark are printed on an envelope.

Die Cut - a modern method of separating self-adhesive stamps.  A cut completely penetrates the paper all around the stamp, making it possible to remove individual stamps from the liner that is underneath.  Die cuts can take a variety of shapes, including straight lines, and wavy lines that simulate traditional perforations.

Die Cut Gauge - 1.) a number that equals the total quantity of serpentine peaks (or valleys) within the space of 20mm on die cut stamps.  2.) a tool that measures the total quantity of serpentine peaks (or valleys) within the space of 20mm on die cut stamps.  Compare: Perforation Gauge.

Die Flaw - an imperfection that existed on the surface of a blank die before the die was engraved.  Such imperfection can appear on the printed stamps.

Die Proof - a printed impression made directly from a die.  See also: Large Die Proof and Small Die Proof.

*Directory Markings - postal markings applied to a cover by postal workers indicating a failed attempt to deliver mail, such as "Address Unknown" or "Forwarding Time Expired".

Discontinued Post Office - a post office no longer in operation.

Disinfected Mail - mail that has been treated to prevent the spread of a contagion.  Also see Irradiated Mail.

Distilled Spirits Stamp - revenue stamp for payment of taxes on distilled spirits.  Used from 1950-1959.  Scott RX.

Dittler Brothers, Inc. - private printer of postage stamps.  Their first stamp was the green denominated 29¢ Eagle and Shield of 1992, Scott 2596.

Doane Cancel - a duplex handstamp, common in the early 20^th century, containing a numeral as a part of the cancel.  The numeral indicates the annual compensation of the postmaster.  For example, a number 5 in the cancel means that for the year prior to the issuing of the handstamp, the postmaster's annual compensation was between $400 and $499.

Docketing - notation written on a cover by the recipient.  Docketing sometimes helps establish the date of a cover.

*Documentary Stamps - revenue stamps used to pay a federal tax on certain transactions that are documented on paper.  The stamps were attached to the documents.  They were first used in 1862 to help pay for the Civil War.  Scott catalogue numbers begin with R.

Domestic Mail - mail that never leaves the mailstream of the United States, as opposed to International Mail.

Doremus Machine Co. - major manufacturer of cancelling machines in use from the 1890s to the 1930s.

Double Grill - a stamp  grilled twice.

Double Impression - a stamp on which the design, or a portion of the design, is doubled.  This phenomenon occurs when a sheet slips against an offset blanket, or when the press is stopped, relaxing the tension on the web.  Double impressions are freaks.  A double impression is not the same thing as a double printing or double transfer.

Double Joint Line - a joint line on rotary press  stamps that appears to be two parallel lines.  This appearance is caused when the gap between the two rotary plates is somewhat wider than normal.

*Double Line Watermark - a watermark in which the initials USPS are composed with double lines.  In other words, the initials USPS are outlined and hollow.  Example: Scott 264.

Double Paper - a stamp printed on two layers of paper.  There are two distinct causes of double paper: 1.) a double paper was intentionally used on some stamps by the Continental Bank Note Co. in the course of printing its Large Banknote stamps of 1873.  2.) double paper resulted on some rotary press stamps when a tear or cut in the web was repaired with a splice.  Splicing required some overlapping of the web, hence creating a double paper variety.  Double paper varieties were also created when two webs were attached.

Double Perforation - a stamp or multiple with an extraneous row of perforations; such stamps are considered to be freaks, not errors.

Double Printing - a stamp that has passed through the press twice.

Double Transfer - a plate variety in which a portion of the design is doubled, that is, it appears twice.  A double transfer occurs on engraved stamps when a design is "rocked" into a plate from a transfer roll in such a way that the rocked images are out of alignment.  Thus, if the siderographer is not careful, the rocking in of the design will cause a part of the design to appear more than once.  Sometimes a double transfer on a plate is discovered and the double transfer is "burnished" out.  But if this process is not totally successful, some amount of doubling of the design may remain.  All sheets printed from a plate with a double transfer will show the double transfer.  That is, the double transfer will be a constant variety.

Drop Letter - a letter mailed at a post office for delivery to another patron at the same office.  Drop letters were charged less than letters that required dispatch to a different post office.

Dropped Mail - mail dropped from an aircraft for forwarding to its destination.

Dropped Transfer - 1.) an impression on an engraved printing plate caused when a transfer roll accidentally touches the blank plate before being properly positioned.  This results in a narrow band of doubling across the design.  2.) one or more entries on a plate that are lower than intended, and lower than the other entries on the plate.

Dry Printing - the printing of intaglio stamps on paper with low moisture content.  Dry printing was first used at the BEP in 1953.  All Bureau Issues has been dry printed since the late 1950s.  Compare: Wet Printing.

Duck Stamps - revenue stamps, officially known as "United States Migratory Bird Hunting and Conservation" stamps, issued annually, and required to be signed by hunters and affixed to their hunting licenses.  Collected both on and off license.  Scott RW.

Dumb Cancel - see Mute Cancel.

Dummy Booklet - see Dummy Stamps.

Dummy Coil - see Dummy Stamps.

Dummy Stamps - stamp-like labels either without denomination or with a value shown that has a defacement line through it.  Such stamps were used for training and testing purposes.  Produced in sheet, coil and booklet format.  These "stamps" have no postal value or validity.

Duplex Cancel - 1.) a single unit handstamp uniting both a postmark and a cancel.  First introduced in the 1860s and in use through the 1940s.  2.) the impression left by a duplex cancel handstamp on a cover.

*Durland - abbreviated term for Durland Standard Plate Number Catalog, the authoritative catalog of plate numbers originally published by Clarence Durland beginning in 1950, and now edited and published by the United States Stamp Society.