that of a collecting pipe, and as
the aggregate area of the holes in it is greatly in excess of the area
of the steam outlet from the drum, it is plain that there can be no
restriction through this collecting pipe. It extends nearly the length
of the drum, and draws steam evenly from the whole length of the steam
space.

[Illustration: Cast-iron Vertical Header Longitudinal Drum Babcock &
Wilcox Boiler]

[Illustration:
Closed Open

Patented Side Dusting Doors]

The large tube doors through which access is had to the front headers
and the doors giving such access to the rear headers in boilers of the
vertical header type have already been described and are shown clearly
by the illustrations on pages 56 and 74. In boilers of the inclined
header type, access to the rear headers is secured through the chamber
formed by the headers and the rear boiler wall. Large doors in the sides
of the setting give full access to all parts for inspection and for
removal of accumulations of soot. Small dusting doors are supplied for
the side walls through which all of the heating surfaces may be cleaned
by means of a steam dusting lance. These side dusting doors are a
patented feature and the shutters are self closing. In wide boilers
additional cleaning doors are supplied at the top of the setting to
insure ease in reaching all portions of the heating surface.

The drums are accessible for inspection through the manhole openings.
The removal of the handhole plates makes possible the inspection of each
tube for its full length and gives the assurance that no defect can
exist that cannot be actually seen. This is particularly advantageous
when inspecting for the presence of scale.

The materials entering into the construction of the Babcock & Wilcox
boiler are the best obtainable for the special purpose for which they
are used and are subjected to rigid inspection and tests.

The boilers are manufactured by means of the most modern shop equipment
and appliances in the hands of an old and well-tried organization of
skilled mechanics under the supervision of experienced engineers.

[Illustration: Cast-iron Vertical Header Cross Drum Babcock & Wilcox
Boiler]

ADVANTAGES OF THE BABCOCK & WILCOX BOILER

The advantages of the Babcock & Wilcox boiler may perhaps be most
clearly set forth by a consideration, 1st, of water-tube boilers as a
class as compared with shell and fire-tube boilers; and 2nd, of the
Babcock & Wi