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chinery and all of the coal and lignites to be tested, should be furnished to the government free of charge.

Considerable delay in equipping the plant was occasioned by these provisions, as it was necessary to induce a large number of manufacturers to incur the expense of providing the equipment necessary to carry on the work. Labor strikes at some of the factories supplying the equipment occasioned a still further delay, and the plant was not put in operation until September 1, 1904.

The railroad companies entering St. Louis, or having coal resources along their lines have coöperated most heartily in these investigations, a preliminary report of which may be obtained upon application to the director of the United States Geological Survey.

This exhibit and the Collective Portland Cement Exhibit and Model Testing Laboratory of the Association of American Portland Cement Manufacturers, which is fully described in the paper on the subject, by Mr. Richard L. Humphrey, formed two very interesting features of the exposition. They were working exhibits and accomplished much good in an educational way, besides yielding valuable data relative to fuels and the various building sands and gravels of this country, and were supported with funds available only for the period of the exposition.

The important results obtained and to be secured through a continuance of the work led to an earnest appeal to Congress on the part of those interested in the work which resulted in a liberal appropriation for the continuance of the investigation of fuels and structural materials on a much more extensive plan. With the appropriation for structural materials which be

properties. For the strength tests, a clear, straightgrained, well-seasoned, white pine plank, 16 inches broad and 13 inches thick, having a little sap-wood in two outer corners, was used (Fig. 4). Specimens from this plank were tested under three conditions of moisture, viz.: "Dry," specimens dried over a boiler one week; "Normal," specimens tested as cut from the plank; and "Wet," specimens kept under water one week. There being six laboratory divisions, the plank was cut so as to give six endwise compression specimens in its width (Fig. 4). Thus, specimens Nos. 1 Dry, No. 7 Normal, and No. 13 Wet, representing the three moisture conditions, and all from similar positions with respect to the center of the tree, were tested in the first laboratory division (Fig. 5). The next three specimens, in the second division (Fig. 6), and so on (Figs. 7, 8, 9 and 10). These three tests, with full data as to loads and shortenings, were easily finished within the hour. The shortening was measured with a Brown and Sharpe test indicator as shown in Fig. 11. This instrument reads directly to thousandths of an inch, but ten-thousandths may be estimated with fair degree of accuracy. The method of measuring between compression blocks proves sufficiently accurate if a small initial load be applied before taking the first reading.

In same manner, during the laboratory periods of the following two weeks, the remainder of the tests (Fig. 4), consisting of across grain compression (Figs. 12, 13 and 14), endwise tension, across grain tension, and along the grain shear, were completed; each student following a strip of the plank throughout its length through all these tests.

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