Several methods of hand coloring are in use, each having peculiarities that 

 are advantageous under certain circumstances. 



Crayon Pencils 



These wax-base colored pencils are applied as evenly as possible over the 

 surface of the sheet with particular attention being given to boundary margins. 

 When all areas of one color have been covered, a fine, even tone of clear color 

 is achieved as follows: It is necessary to have at hand a few paper charcoal 

 stumps (blenders) of sizes 4 to 8, which can be purchased at any artists' supply 

 store. The stump is dipped in white gasoline, benzine, or dry cleaning fluid; and, 

 after the excess on the surface has soaked in, the stump is rubbed over the 

 penciled area with a light, fast circular motion. The solvent dissolves the wax 

 and carries the pigment into the absorbent paper. This process produces a water- 

 resistant color on the map. When the solvent in the map paper has evaporated, 

 a second application of color and solvent may be applied if darker tones are 

 desired. A dark tone can be graded imperceptibly into a lighter one in this 

 manner; or two colors may be so graded, one into the other. After the wax- 

 pencil coloring has been treated with solvent, it has no tendency to rub off. 



Indelible Pencils 



The indelible colored pencil, sometimes called a water-color pencil, is soluble 

 in water but is relatively unaffected by the aromatic solvents used with the wax- 

 base pencils. The method of application is identical to that described above, 

 except that the blender is used dry. The indelible pencil spreads easily and 

 rapidly with either a dry stump or a wad of facial cleansing tissue or blotting 

 paper. 



For temporary maps, the indelible pencil is better than the crayon pencil. 

 The indelible pencil is especially useful in preliminary work which may have to 

 be revised, for the color can be removed with a soft rubber eraser even after 

 blending with a stump. On the other hand, it rubs off on clothing or other maps, 

 and changes to brilliant hues on contact with even small amounts of water. Per- 

 spiration from the hands will cause unsightly blotches on the map; therefore, 

 when there is danger of this blotching, colored portions should be covered while 

 work is in progress. The color can be fixed, or set, by spraying with Krylon 

 liquid plastic. 



Water Color 



Transparent water colors may be applied as a wash on Ozalid prints, but 

 they are difficult to use and may cause appreciable shrinkage and distortion of 

 the map scale. The air brush is an efficient and generally satisfactory method, 

 although it may cause some shrinkage. When using the air brush, one should 



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