The following brands of paper are used in the Survey in the preparation of maps: "Normal" K. & E., unmounted. Has an excellent surface and comes in flat sheets, 19 by 24, 22 by 30, and 27 by 40 inches. "Paragon" K. & E., mounted on muslin. In 10-yard rolls 72 inches wide. Used in the Survey for large office drawings and maps of large scale. "Anvil" K. & E., mounted on muslin. In 10-yard rolls 42, 62, and 72 inches wide. Used in the Survey for large drawings. "Whatman's hot pressed," unmounted or mounted on muslin. In sheets ranging in size from 13 by 17 to 31 by 53 inches. An excellent paper for maps. The muslin-backed paper is recommended for use in preparing large detailed maps and base maps that are to be retained as permanent records. The muslin provides a durable and flexible backing that permits the map to be rolled, and paper thus mounted is particularly serviceable for a map which may be subjected to considerable revision and to which must be added finally a title, explanation, and other marginal matter. "Ross's relief hand-stipple drawing paper." A stiff enameled or chalk-coated paper whose surface has been compressed into minute points that stand in slight relief so that a shade made on it with pencil or crayon is broken up into dots and can be reproduced by photo-engraving. For use in making shaded drawings, drawings showing relief by light and shade, etc. Similar paper is prepared for parallel-line and other pattern effects. In sheets ranging in size from 11 by 14 to 22 by 28 inches. (See p. 51 for method of using.) Profile and cross-section paper. In sheets of convenient sizes or in rolls. Bears lines printed in blue, green, red, or orange, in many kinds of rulings, which may be selected by reference to catalogues. Profile and cross-section paper printed in orange is recommended for preliminary drawings; blue is recommended for drawings that are made in pencil and submitted for inking in. BRISTOL BOARD. For the smaller maps, such as key maps and maps less than 18 by 24 inches, and for small drawings made for direct reproduction, Reynolds's bristol board is recommended on account of its pure-white color and its hardness, which permits erasures to be made without affecting redrawing over the corrected area. It is obtained in 2-ply, 3-ply, and 4-ply sheets. The 2-ply and 3-ply are especially useful in making delicate brush and pencil drawings and pen and ink drawings. The sizes used in the Survey are 16-1/2 by 20-3/4, 18-1/4 by 22-3/8, and 21-1/2 by 28-3/4 inches. TRACING LINEN.