o the steam, and
that, too, with the least amount of waste heat in giving a natural draft.
Hence the great economy of this boiler.

The next feature of this engine is, it has no wood work about it to perish
with the heat and roughness of the streets. All the wheels are wrought
iron; and, as yet, these are the only ones that have stood a steam fire
engine. The frame is wrought iron; truck, on which the front wheel is hung,
wrought iron. The axles are cast steel. The engine and pump is a
double-acting piston pump direct, without any rotary motion; with a
perfect balance valve, it is balanced at all times, and hence the engine
remains quiet without blocking, when at work. The engine is mounted on
three wheels, which enables it to be turned in a very short space.

Many engines have been constructed by the Messrs. Latta for the fire
companies, of different cities, and have been in successful competition
with other engines; the farthest throw ever made by one of their
first-class engines was 310 feet from a 1-5/8 inch nozzle; steaming time,
starting from cold water, 3-1/2 minutes.

[Illustration: Fig. 74 AMOSKEAG STEAM FIRE ENGINE.]

Fig. 74 is a representation of one class of steam fire engine, as built by
the Amoskeag Manufacturing Company, at Manchester, N.H. The boiler is an
upright tubular boiler, of a peculiar construction, the patent right to
which is vested in the Amoskeag Manufacturing Company. This boiler is very
simple in its combination, and for safety, strength, durability, and
capacity for generating steam is unsurpassed. No fan or artificial blower
is ever used or needed, the natural draft of the boiler being always
sufficient. Starting with cold water in the boiler, a working head of steam
can be generated in _less than five minutes_ from the time of kindling the
fire. The engine "Amoskeag," owned by the city of Manchester, has played
two streams in _three minutes and forty seconds_ after touching the match,
at the same time drawing her own water. The boilers are made and proved so
as to be safely run at a steam pressure of 140 to 150 lbs. to the square
inch; but the engines are constructed so as to give the best streams at a
pressure of about 100 lbs. to the square inch, and for service at fires a
steam pressure of about 60 lbs. to the square inch is all that is required.

The various styles of engine are all _vertical_ in their action, and in all
the pumps and steam cylinders are firmly and directly faste