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 as far as possible, by showing the more thickly crowded district as a separate area on a larger scale placed at one side of the map.

"Modern Philanthropy", W. H. Allen, Dodd, Mead & Co.

Fig. 200. Sources of the First 3,000 Letters of Appeal Sent to Mrs. E. H. Harriman. These 3,000 Letters Asked for $70,000,000

Eight different kinds of pins were used on this map to represent different kinds of appeals. Long pins like those seen here are apt to fall out of the map, and thus destroy the accuracy of the record. Note the area around New York shown on a larger scale at the right

The use of beads in conjunction with pins overcomes the main difficulties encountered when pins alone are used. Beads may be placed one above each other on long pins or wires so that each pin will be exactly in the point on the map for each city, and thus portray numerical data by map location more accurately than possible with other methods. The adjoining cities can be clearly discerned by means of separate columns of beads, whereas if pins alone are used the different groups of pins frequently blend so as to be indistinguishable. If there is only one item to be represented in a town, single glass-head pins may, of course, be used in conjunction with the beads.

When there are several units in a town, the beads strung on a long pin or wire can be counted quickly if a bead of a different color is used for every tenth bead, so the whole column may be counted by tens as possible in Fig. 201. A bead map like Fig. 201 should be mounted on several layers of corrugated straw-board to allow the long pins sufficient depth in the mounting to hold fast. For this