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The care and management of a steam boiler comprises three things:

1. The preparation, which includes the partial filling with water and the kindling of the fire.

2. The running, embracing the feeding, firing and extinction or banking of the fire.

3. The cleaning out after it has been worked for some time.

To do this to the best advantage, alike to owner and employee, can be learned only by practice under the tuition of an experienced person. The “trick” or unwritten science of the duties of the skillful fireman must be communicated to the beginner, by already experienced engineers or firemen or from experts who have made the matter a special study. Let it be understood that the art of firing cannot be self taught.

The importance of this knowledge is illustrated by a remarkable difference shown in competitive tests in Germany between trained and untrained firemen in the matter of securing a high evaporation per pound of coal. The trained men succeeded in evaporating 11 lbs. of water, as against 6.89 lbs. which was the best that the untrained men could obtain.

It is certain that a poor fireman is a dear man at any price, and that a competent one may be cheap at twice the wages now paid. Suppose, for instance, a man who burns three tons a day is paid $2.00 for such service, and that in so doing he is wasting as little as 10 per cent. If the coal cost $4.50 per ton the loss will be $1.35 per day, or what is equivalent to paying a man $3.35 per day who can save this amount.

The late Chief Engineer of Philadelphia Water Works effected an annual saving to the city of something like $50,000; and recently the weekly consumption of a well established woolen mill was reduced from 71 to 49 tons, a clear saving of 22 tons by careful attention to this point.

It is apparent that any rules or directions which might be given for one system would not apply equally to other forms of boilers and this may be the principal reason that the art is one so largely of personal instruction. Some rules and hints will, however, be given to the beginner, which may prove of advantage in fitting the fireman for an advanced position; or to assure him permanence in his present one.

No two boilers alike. It is said that no two boilers, even though they seemed to be exactly alike—absolute duplicates—ever did the same, or equal service. Every steam boiler, like every steam engine, has an individuality of its own, with which the person in charge has to become acquainted, in order to obtain the best results from it.

The unlikeness in the required care of steam engines which seem to be exactly the same, is still more marked in the different skill and experience demanded in handling locomotive, marine, stationary, portable boilers and other forms of steam generators.

Before Lighting the Fire under the boiler in the morning, the engineer or fireman should make a rapid yet diligent examination of various things, viz.: 1. He should make sure that the boiler has the right quantity of water in it—that it has not run out during the night or been tampered with by some outside party; very many boilers have been ruined by neglecting this first simple precaution. 2. He should see that the safety-valve is in working order; this is done by lifting by rod or hand the valve which holds the weight upon the safety valve rod. 3. He should open the upper gauge-cock to let out the air from the boiler while the steam is forming. 4. He should examine the condition of the grate-bars and see that no clinkers and but few ashes are left from last night’s firing. 5. And finally, after seeing that everything is in good shape, proceed to build the fire as follows:

On Lighting the Fire. When quite certain that everything is in good condition, put a good armful of shavings or fine wood upon the grate, then upon this some larger pieces of wood to form a bed of coals, and then a little of the fuel that is to be used while running. Sometimes it is better to light before putting on the regular fuel, but in any case give it plenty of air. Close the fire doors, and open the ash pit, giving the chimney full draught.

When the fire is well ignited, throw in some of the regular fuel, and when this is burning add more, a little at a time, and continue until the fire is in its normal condition, taking care, however, not to let it burn too freely for fear of injury to the sheets by a too rapid heating.

It is usually more convenient to light the fire through the fire door, but where this cannot be done, a torch may be used beneath the grates, or even a light fire of shavings may be kindled in the ash pit.

At the time of lighting, all the draughts should be wide open.

As soon as the steam is seen to issue from the open upper gauge-cock it is proof that the air is out. It should now be closed and the steam gauge will soon indicate a rise in temperature.

When the steam begins to rise it should next be observed that: 1. All the cocks and valves are in working order—that they move easily. 2. That all the joints and packings are tight.

In the following two cuts are exhibited in an impressive way the difference between proper and improper firing.

Fig. 1.

Fig. 1 represents the proper mode of keeping an even depth of coal on the grate bars; the result of which will be, a uniform generation of gas throughout the charge, and a uniform temperature in the flues.

Fig. 2.

Fig. 2 represents a very frequent method of feeding furnaces; charging the front half as high, and as near the door, as possible, leaving the bridge end comparatively bare. The result necessarily is that more air obtains access through the uncovered bars than is required, which causes imperfect combustion and consequent waste.

The duties of the fireman in the routine of the day may thus be summed up:

1st.—Begin to charge the furnace at the bridge end and keep firing to within a few inches of the dead plate.

2d.—Never allow the fire to be so low before a fresh charge is thrown in, that there shall not be at least three to five inches deep of clean, incandescent fuel on the bars, and equally spread over the whole.

3d.—Keep the bars constantly and equally covered, particularly at the sides and the bridge end, where the fuel burns away most rapidly.

4th.—If the fuel burns unequally or into holes, it must be leveled, and the vacant spaces must be filled.

5th.—The large coals must be broken into pieces not bigger than a man’s fist.

6th.—When the ash pit is shallow, it must be the more frequently cleared out. A body of hot cinders, beneath them, overheats and burns the bars.

7th.—The fire must not be hurried too much, but should be left to increase in intensity gradually. When fired properly the fuel is consumed in the best possible way, no more being burned than is needed for producing a sufficient quantity of steam and keeping the steam pressure even.