The words used to describe maps can be a bit daunting at first. MAPSandART.com has compiled for you some important terms used in antique map collecting circles, to make things clearer.
Age Toning = browning of the paper due to chemical changes.
Backed = when a map is glued onto something else to give it stength and durability. Folding maps and wall maps often have a backing to avoid damage. Backing should use archival materials that are reversible and not deteriorate the map over time.
Bird’s-Eye View = an aerial view of a city or town.
Bleaching = use of bleach-like chemicals to whiten paper. Bleaching should be done by experienced professionals.
Border = this is different from a margin. A border is the outer limit of a map. It can either be decorative or just a neat line.
Browning = a darkening of the paper due to pollutants in the air, acid from non-archival framing materials or from direct sunlight of fluorescent light. Strong browning is also a sign that the paper may be brittle. Keep in mind that images of maps on the web may be darker than they actually are because of the lights used to photograph the map.
Cartouche = a decorative element on the map that contains important information such as the scale and the title of the map. Cartouche is from the French meaning cartridge or seal. It will usually depict plants, scenery and people relating to the map, but can also just be a geometrical form surrounding the title information.
Centerfold = a fold usually in the middle of the map where it was inserted in an atlas and bound. There are often small repairs on the top or bottom of a center fold because of tears due to the usage.
Chain Lines = are the lines made during the manufacture of old paper in the form of a grid of wires called wire lines. Hold up the paper to a source of light to see the chain lines as well as the possible watermark of the paper manufacturer. Such paper is found on maps from the 1830s and earlier.
Coloring = refers to the actual colors applied to the map either mechanically or by hand. Early maps prior to the 1860s were mostly hand colored.
Compass Rose = a symbol used to show direction. North is usually indicated with a pointer.
Contemporary = denotes the time when the map was published, therefore contemporary hand coloring refers to coloring done at the time the map was made.
Decorative = refers to esthetic elements on the map, such as plants, animals, buildings and such.
Engraving = a printing method in which the image of a map is carved out of a metal plate in reverse allowing it to be inked and printed on paper.
Etching = another printing method where the image of a map is scatched on a metal plate that had a varnish-like coating. The metal plate is then exposed to acid. This acid “bites” the areas scratched away creating a groove. The grooves hold the ink for printing giving us an etching.
Folio = is a size of paper which is usually longer than 11 inches.
Foxing = small brown spots of varying intensity which are caused by mold found on a map following storage in a damp environment.
Gore = is a oval shaped section of a globe.
Inset = is a smaller map set within a larger map.
Laid Down = same as backing (see backing).
Laid Paper = handmade paper made of cloth fibers. During the paper-making phase the cloth fibers are immersed in water and a grid of thin wires holds the paper when removed from the water. Upon removal, a grid pattern is created that can be seen against a light source. This grid is called chain marks, or chain lines. (see chain lines).
Lithograph, Lithography = is a printing method very commonly used from the 19th century onwards that utilizes a stone to create an image of the map in reverse, which is then printed (see lithography article under articles section).
Margin = the unprinted area around the map. This is different from the border. When we give dimensions for the paper of a map we are refering to the outer margins.
Mercator Projection = designed to solve problems of navigation by putting longitude and latitude in the form of a grid.
Meridian = is an imaginary line linking the North to South pole on which latitudes are given. Greenwich is our prime meridian today, however Paris, Rome and even Washington D.C. were used on older maps as prime meridians.
Mounted = see backed.
Neat Lines = straight lines that surround the image of the map
Octavo = is the size of the paper which was bound in a book. Octavo is paper that has been folded in half three times and is usually about 8 inches long (20 cm).
Offsetting = is when a map has been in contact with another page for a long time and there has been a transfer from one page to the other.
Original = means that it is not a recent reproduction.
Outline Color = coloring of only the boundaries and/or coastlines of a map.
Plate Mark = when a map is printed from a metal plate a large amount of pressure is applied to it in the press. The metal plate will then leave a plate mark which will be the outer edge of the printed map.
Portolan Chart = old sea charts drawn by hand before the 16th century.
Printer’s Crease = when printing a small fold may occur in the paper which is printed upon.
Quarto = the size of paper that has been been folded two times to be inserted in a book. The size is usually about 9 to 11 inches long (23 to 28 cm).
Reproduction = a copy of an original map. MapsAndArt.com only sells originals, never any reproductions
Restrike = a map that was reprinted using the original plate.
Rhumb Lines = Lines on old maps crossing at different angles that usually follow the points on a compass. Navigators used rhumb lines to plot their course.
Wall Map = a very large map that was usually backed with linen to allow it to be hung on a wall. These are usually over 5 feet long (1.6 m) and often damaged.
Watermark = when making paper the manufacturer would insert their name or symbol in the thin wires that hold the paper (chain lines). Watermarks are very useful in determining the age of a map.
Wood Engraving = is a method of printing that appeared only in the 19th century that used the end grain of the wood and therefore was limited to the diameter of the tree trunk. For larger maps several wood engravings would be tied together to print the map.
Wormholes = think of book worms. These are holes or tracks left by larvae that eat paper.