beled out for several courses, forming a ledge, around the
outside of which is placed a wrought-iron railing, thus forming a
walkway around the circumference of the chimney top. The cap is of
cast iron, surmounted by eight 3 x 1-inch wrought-iron ribs, bent over
the outlet and with pointed ends gathered together at the center. The
lightning conductors are carried down the outside of the shaft to the
roof and thence to the ground outside of the building. Galvanized iron
ladder rungs were built in the brickwork, for ladders both inside and
outside the shaft.

The chimneys, except for the octagonal red-brick base, are constructed
of the radial perforated bricks. The lightning rods are tipped with
pointed platinum points about 18 inches long.

[Sidenote: _North River
Pier_]

Exceptional facilities have been provided for the unloading of coal
from vessels, or barges, which can be brought to the northerly side of
the recently constructed pier at the foot of West 58th Street. The
pier was specially built by the Department of Docks and Ferries and is
700 feet long and 60 feet wide.

The pier construction includes a special river wall across 58th Street
at the bulkhead line through which the condensing water will be taken
from and returned to the river. Immediately outside the river wall and
beneath the deck of the pier, there is a system of screens through
which the intake water is passed. On each side where the water enters
the screen chamber, is a heavy steel grillage; inside this is a system
of fine screens arranged so that the several screens can be raised, by
a special machine, for the purpose of cleaning. The advantages of a
well-designed screening outfit has been appreciated, and considerable
care has been exercised to make it as reliable and effective as
possible.

At each side of the center of the pier, just below the deck, there are
two discharge water conduits constructed of heavy timber, to conduct
the warm water from the condensers away from the cold water intakes at
the screens. Two water conduits are employed, in order that one may be
repaired or renewed while using the other; in fact, the entire pier is
constructed with the view of renewal without interference in the
operation for which it was provided.

CHAPTER IV

POWER PLANT FROM COAL PILE TO SHAFTS OF ENGINES AND TURBINES

From the minute and specific description in Chapter III, a clear idea
will have been obtained of the power house build