Instructions for Setting up, Properly Attaching, and Adjusting Injectors.

All pipes, whether steam, water-supply, or delivery, should be of the same internal diameter as the hole in the corresponding branch of the injector, and as short and straight as practicable. When floating particles of wood, or other matter, are liable to be in the supply-pipe, a strainer should be placed over the receiving end of it. The holes in this strainer should be as small as the smallest opening in the delivery-tube, and the total area of all the holes should be greater than the area of the water-supply pipe, to compensate for the closing of some of them by deposits.

The steam should be taken from the highest part of the boiler, in order to avoid the carrying over of water with the steam; but it should not be taken from the pipe leading to the engine, unless such pipe is large.

When any injector capable of raising water is set, care must be taken to have the pipes as tight as possible, so as not to draw air.

If the water is not lifted by the injector, but flows to it from a tank or hydrant, there should be a cock in the water-supply pipe; and in case the injector be self-adjusting, this cock should be of a kind that will prevent any considerable pressure in the watersupply pipe between it and the injector. The higher the steam is carried in the boiler, the greater may be the pressure in the water-supply pipe.

There should always be a stop-valve or cock in the steam-pipe, between the steam-space in the boiler and the injector, and a check-valve between the water-space of the boiler and the injector.

When an air-chamber is placed below the injector in the watersupply pipe, care should be taken to keep it supplied with air. When the injector lifts water from a tank placed below it, no precaution is needed, as, when the injector is stopped, the water flows back and air enters the pipe.

When fed from a hydrant through a self-regulating valve, there should be a pet-cock between the valve and the air-chamber, which will serve to drain away the water when the valve is closed and the injector is not working.

After all the pipes are properly connected to the injector and to the boiler, and it is ready for work, they should be disconnected and well washed out, in order to remove any obstructions, such as paint, red lead, straw, or shavings, that may have found their way into them. Many excellent instruments have been condemned because those who set them up failed to take this precaution.

Injectors, like pumps and other hydraulic machines, are not so reliable in action when working water of a high temperature as when the temperature is moderate; though there are several injectors, owing to peculiarities in their mechanical arrangements, more reliable in this respect than others.

Injectors, like nearly all other machines connected with steamboilers, are frequently neglected, and allowed to become covered with filth, which, in view of their wonderful utility and efficiency, is a reproach to those who have them in charge.

The Ejector or Lifter.

The annexed cut represents the ejector or lifter, which is practically the lifter side of the inspirator, with a reduced steam-jet and enlarged lifter combining-tube. It is suitable for breweries,

tanneries, bleacheries, etc.; for transferring large volumes of water, lye, acid, and other liquids. It will deliver more fluid of any kind at a low lift, with a lower pressure of steam, than either the injector or inspirator; but it is not as reliable, or as well adapted to the dif ferent purposes for which these instruments are used, as either of them. It answers a very good purpose when cellars become flooded in consequence of heavy rain-falls, high tides, or overflowing of culverts, and requires no very intelligent management. Its action is based on the DELIVERY same principle as that of the injector, and is more simple, as it has no adjustable or movable parts.

Method of starting the ejector. -All that is necessary to start the ejector is to turn on the steam, after which it will work as long as the water-supply and steam-pressure continue; and it is immaterial what lift it is started on, as the steam-supply may be gradually reduced to meet the requirements of the quantity of water to be discharged. If started on a steam-pressure of 40 lbs. per square inch, it will continue to work until the pressure falls to 15 pounds.

The Ejector and Inspirator are manufactured by the Hancock Inspirator Co., Boston, Mass.

Jamison's Steam Water-Ejector.

The annexed cut represents Jamison's steam water-ejector, as it is termed, which, like other ejectors, is suitable in tanneries, breweries,

or places where large quantities of liquids which contain floating particles, such as malt, hops, bark, sawdust, etc., require to be lifted, as it has no moving mechanism to be obstructed or clogged. Its action is based on the same principle as the steam siphon, and when once started, by simply turning on the steam, it will continue to work as long as the steam and water-supply lasts, through a diminution of pressure ranging from 15 to 100 lbs. per square inch, and vice versa. As they are generally made of brass or some non-corrosive metal, they rarely ever wear out or require any attention. They are just as efficient when submerged in water or other liquid as when directly on the surface.

TABLE

Questions,

THE ANSWERS TO WHICH WILL BE FOUND IN THE TEXT.

What is the object of attaching a condenser to a steam-engine?

Give the names, and the advantages and disadvantages of the two kinds of condensers in most general use, with a description of the same.

Explain how the injection-water enters and escapes from surface and jet condensers.

State what relative proportion the jet condenser should bear to the steam-cylinder of a condensing engine.

State what relative proportion the cooling surface in a surface condenser should bear to the cubic contents of the steam-cylinder.

State the respective advantages and disadvantages of having condensers too large or too small.

What is the most advantageous temperature at which to keep the water in hot wells? and what effect does too high or too low a temperature exert on the economical working of the engine?

Explain the arrangements by which the bilge injection-water is introduced into jet and surface condensers.

What would be the effect of not shutting off the injection-water when the engine is stopped?

State the quantity of water necessary to condense steam, with a formula.

Give the rule for finding the cooling surface in the tubes of surface condensers.