hose laid and ready to work:  that is, supposing the fire to be within one square of the place where the steamer is located.  The object in locating a machine at any point is to protect that immediate vicinity; and it is therefore absolutely necessary to have it available in the shortest space of time, and that with unerring certainty.  We think that reliability is of the greatest importance to the protection of a city from fire, as everything is dependent on the working of such apparatus in time; and for this reason no expense should be spared on this kind of machinery.”

Fig. 73 is a representation of one of the Messrs. Latta’s fire engines, of which there are many of different classes, according to the requirements; they say that they can furnish engines as low as $1,000, and have made some for $10,000.

The first peculiar feature of this engine is the boiler; it differs entirely from all boilers now in use.

[Illustration:  Fig. 73.]

The fire box or furnace is simply a square box or furnace of any required dimensions; it is nothing more than a water space surrounding the fire, stay-bolted as all water spaces are.  It is made of boiler plate in the usual manner.  The water space extends only 2/3 of the height, the balance being a single sheet.  The bottom of this fire box is crossed by grate bars to support the fuel; in its rear side are fire doors, inserted for firing.  The internal arrangements of the boiler are composed of a large number of tubes, lying across in a horizontal position, put together in sections with return bends resembling the coils for heating buildings.  These coils are of small pipe (say one inch in diameter), and as numerous as may be necessary.  They give the required amount of steam.  They are secured to wrought-iron plates at each end by rivets.  These plates lie close to the box, and are secured to it, top and bottom.  These tubes are wrought iron, firmly screwed into the bends, so as to prevent any possible breaking.

The box has a hole through both sheets, in the same manner as a hollow stay-bolt, through which the coil pipe passes, having no connection with the box.  After passing into the box it divides into two pipes, then subdivides into four, and so on, until its numbers equal the number of coils in the box, and to which each limb is attached.  The upper ends of these coils are the same in number, and are carried through at the top or nearly the top of the box.  They then run down outside to the steam chamber, or rather water space, as the box is both steam chamber and water space.  These pipes empty their contents into the box, steam and water, as it may come, all together.  It will be observed that these coils of tube are sufficiently separated to allow the fire to pass between them freely, and cover their whole surface.

The mode of operation of this boiler is this:  The fire box is filled 2/3 full of water.  The coils are dry at starting; the space for fuel being filled with good wood, the fire is lighted, and in a few moments the engineer moves his hand pump, which takes its water from the box to which it is attached, and forces it through the coils.  By this means steam is generated in from 3 to 5 minutes, so as to start the engine.