Here it is a Diesel, started by President Wilson by wireless on the
opening day, and generating all the direct current used in the palace.
Another commanding exhibit is a 20,000 horsepower hydro-electric
generator, significant of the modern use of water-power. The United
States Government is the largest exhibitor in the building, with
numerous fine models of warships, docks, dams and submarine mines;
torpedoes, artillery, armorplate and shells, army equipment,
ammunition-making machinery in operation, light-houses and aids to
navigation, and a splendid set of models illustrating road-making
methods. Crowded out of its proper place in the Palace of Liberal Arts,
the exhibit of the printing trades occupies a section here, including a
huge color press turning out illustrated Sunday supplements.

The Palace of Mines and Metallurgy offers ample evidence of the great
figure which steel now makes in the world, and of the vast extent of the
petroleum industry. Here, too, as in Machinery Hall, accident prevention
is emphasized. From this point of view insurance exhibits are not out of
place here. The United States Steel Corporation, with its subsidiary
companies, shows in this palace the largest single exhibit seen in the
Exposition, save those of the United States Government. Noteworthy are
its excellent models of iron and coal-mining plants, coke ovens.
furnaces, rolling mills, docks, ships, and barges, and an extensive
section devoted to the welfare of employees, with model playgrounds.

Many states and nations, and many world-famous mining companies are
represented by exhibits of ores and metals, of mine models, and mining
and metallurgical processes in operation. California shows a gold
dredger and a hydraulic mine in operation. The great copper mines of
California, Montana, Utah, and Japan, have installed significant
exhibits. The United States Government operates in this palace a model