Steam, Its Generation and Use | Page 5

stand-pipe of sufficient height to have the column of water offset the
pressure within the boiler. Watt's attitude toward high pressure made
his influence felt long after his patents had expired.
[Illustration: Portion of 9600 Horse-power Installation of Babcock &
Wilcox Boilers and Superheaters, Equipped with Babcock & Wilcox
Chain Grate Stokers at the Blue Island, Ill., Plant of the Public Service
Co. of Northern Illinois. This Company Operates 14,580 Horse Power
of Babcock & Wilcox Boilers and Superheaters in its Various Stations]
In 1782, Watt patented two other features which he had invented as
early as 1769. These were the double acting engine, that is, the use of
steam on both sides of the piston and the use of steam expansively, that
is, the shutting off of steam from the cylinder when the piston had
made but a portion of its stroke, the power for the completion of the
stroke being supplied by the expansive force of the steam already
admitted.
He further added a throttle valve for the regulation of steam admission,

invented the automatic governor and the steam indicator, a mercury
steam gauge and a glass water column.
It has been the object of this brief history of the early developments in
the use of steam to cover such developments only through the time of
James Watt. The progress of the steam engine from this time through
the stages of higher pressures, combining of cylinders, the application
of steam vehicles and steamboats, the adding of third and fourth
cylinders, to the invention of the turbine with its development and the
accompanying development of the reciprocating engine to hold its
place, is one long attribute to the inventive genius of man.
While little is said in the biographies of Watt as to the improvement of
steam boilers, all the evidence indicates that Boulton and Watt
introduced the first "wagon boiler", so called because of its shape. In
1785, Watt took out a number of patents for variations in furnace
construction, many of which contain the basic principles of some of the
modern smoke preventing furnaces. Until the early part of the
nineteenth century, the low steam pressures used caused but little
attention to be given to the form of the boiler operated in connection
with the engines above described. About 1800, Richard Trevithick, in
England, and Oliver Evans, in America, introduced non-condensing,
and for that time, high pressure steam engines. To the initiative of
Evans may be attributed the general use of high pressure steam in the
United States, a feature which for many years distinguished American
from European practice. The demand for light weight and economy of
space following the beginning of steam navigation and the invention of
the locomotive required boilers designed and constructed to withstand
heavier pressures and forced the adoption of the cylindrical form of
boiler. There are in use to-day many examples of every step in the
development of steam boilers from the first plain cylindrical boiler to
the most modern type of multi-tubular locomotive boiler, which stands
as the highest type of fire-tube boiler construction.
The early attempts to utilize water-tube boilers were few. A brief
history of the development of the boilers, in which this principle was
employed, is given in the following chapter. From this history it will be

clearly indicated that the first commercially successful utilization of
water tubes in a steam generator is properly attributed to George H.
Babcock and Stephen Wilcox.
[Illustration: Copyright by Underwood & Underwood
Woolworth Building, New York City, Operating 2454 Horse Power of
Babcock & Wilcox Boilers]

BRIEF HISTORY OF WATER-TUBE BOILERS[1]
As stated in the previous chapter, the first water-tube boiler was built
by John Blakey and was patented by him in 1766. Several tubes
alternately inclined at opposite angles were arranged in the furnaces,
the adjacent tube ends being connected by small pipes. The first
successful user of water-tube boilers, however, was James Rumsey, an
American inventor, celebrated for his early experiments in steam
navigation, and it is he who may be truly classed as the originator of
the water-tube boiler. In 1788 he patented, in England, several forms of
boilers, some of which were of the water-tube type. One had a fire box
with flat top and sides, with horizontal tubes across the fire box
connecting the water spaces. Another had a cylindrical fire box
surrounded by an annular water space and a coiled tube was placed
within the box connecting at its two ends with the water space. This
was the first of the "coil boilers". Another form in the same patent was
the vertical tubular boiler, practically as made at the present time.
[Illustration: Blakey, 1766]
The first boiler made of a combination of small tubes, connected at one
end to a reservoir, was the invention of another American,