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 losing money unnecessarily, because he does not realize the true cost of work when it is done in only small quantities on different orders.

Fig. 159 proves the great variation in the cost of doing the work of handling a certain class of freight. The position of the dots on the chart shows that work done in orders of only twenty-five packages costs over twice the average for orders of four hundred or over. In keeping track of the cost of handling freight of different kinds for a large steamship terminal and warehouse company it was found impossible to get reliable cost figures by averaging, day by day, the labor cost of handling freight for preceding days. On some days all the orders for one commodity might be small orders, and on the next day a very large quantity of that same commodity might be handled all in one large order, so that a gang of men could work steadily all day on that one order. Naturally if a large gang of men work all day on one order, the cost per package handled would be very much less than if several different gangs were used in handling numerous orders of only ten or twenty-five packages each. In order to get a clear view of what was actually happening, considerable study was given to the problem and the method shown in Fig. 159 is the result.

It was decided to make a pin board about 24 by 30 inches, on the general scheme seen in Fig. 159, by which separate orders could be shown on the chart by a dot to represent each order handled. As it was desired to keep continuous records for the chief commodities, it was not feasible to make ink marks for it would then be necessary to start over again frequently with a completely new sheet of paper. To overcome this difficulty, short pins were used having spherical glass heads only 3/32 inch in diameter like those seen at the right in Fig. 186. The co-ordinate paper for the chart itself was mounted on three layers of corrugated straw-board, having the ribs of the middle layer at right angles to the ribs of the two outside layers, as described in Chapter XII. A binding of gummed cloth-tape around the edge of the board gave a neat appearance and assisted to preserve the boards during rough service and long use. These boards were very light, yet remarkably strong on account of the corrugations running in both directions.

One cost clerk could not possibly figure out the cost of all orders and all commodities handled each day. The cost method was more in the nature of an automatic inspection system or check, so that the general efficiency of the work done by numerous gangs and hundreds of men could be judged by what might be called occasional analyses