SCIENTIFIC UNO WLEDGE AND THE FIRE SER VICE.

SCIENTIFIC UNO WLEDGE AND THE FIRE SER VICE.

THIRD ARTICLE.

From what I have already stated in these articles in general terms, I have indirectly shown how absurd the above proposition is ; but as it is in keeping with the teachings of Captain Shaw that a lesser quantity of water can absorb more heat and exclude more air than a greater quantity under the same conditions, let us take another example: Suppose we take a building of the (size) cube of 60, filled with inflammable materials, and the building to be of the ordinary construction, and locatedln a dangerous location; let this building and contents, some of which are inflammable volatile liquids stored in the top and bottom, but more in the top than the basement ; let the fire originate in the basement, have a good headway and rapidly spreading therein, with some of the tanks, etc., broken, but the flame still confined to the lower portion of the building. What would be the eflect of a quarter-inch jet or a dozen quarter-inch jets on a fire of that class when applied directly to the seat of the burning substances? I wouldn’t like to hold one of those quarter-inch jets, for the following reasons : Assuming, in the first place, that a quarter-inch jet could reach the base and centre of the combustion, the intensity and quantity of the heat would be so great that steam would be generated from the water, and the molecules of the steam would be separated from the influence of their cohesion and resolved into their constituent elementary gases, one of which, science teaches, is a powerful supporter of combustion, the other, one of the most inflammable of the elements, and which generates when burning more heat-units than any other known substance. These gases, when burning, give oflf an intense heat, with a decided change in the flame-volume, which, if the fire spoken of had not already reached the upper portion of the building, would be reached by this augmented volume of flame and gases. What fireman of any experience or even sense would use a quarter-inch jet and direct it at once into the seat of the burning liquids at such a fire? As before stated, at the critical time of this (as well as other classes of intense fires) and while the fire has yet not extended throughout the interior of the building, but from the conditions stated is sure to do so in a few moments, the proper place to apply the jet at this period is not directly upon the seat of the burning liquids, nor is it proper to apply quarter-inch jets to such a fire, when spray or larger ones would give far better results, and if the resources were ample, and if properly applied in accordance with wellgrounded knowledge of the existing action of the natural forces, could prevent the fire from spreading through the entire building by not applying the jet directly to the seat of the combustion. If the building and contents here referred to were situated where its surroundings were such as exist in London’s narrow streets, etc., and there had been but little moisture in the air for several weeks, and buildings all parched, and when this fire got well under way and the air had a velocity of, say, about twenty miles an hour, and this building of the dimensions given (and it is not an extreme case by any means), how many quarter-inch jets would it take, and how near could a fireman approach such a fire to do any execution with such jets? It is needless to contemplate what the result would be.

A fire of this class can certainly be prevented from spreading, if not entirely extinguished, by the water not coming immediately indirect contact with the seat of the burning liquids, and which cannot be done with sixtyfour hand pumps using one-quarter-inch jets. Let us take another aspect of this case. Let us assume the building to be on fire from top to bottom, and that it has got a good headway and has burned through the entire roof, and the velocity of the air the same as that previously stated (twenty miles an hour and dty, etc.), and the fire is spreading rapidly to the adjoining roofs at the leeward side at this moment—and it is assumed all the conditions are favorable for spreading in that direction at this time —a solid two-inch jet, with a pressure of eighty to ninety pounds at the nozzle, situated in a suitable place at the windward side of the fire, would be of more real service in preventing the fire from spreading, riot only in the direction mentioned, but in all others, by directing this jet into the space occupied by theascending highly-heated gases and products of combustion which are produced by the fire. What will be the effect of this jet that does not directly strike the seat of the burning materials ? Science says the effect will be the immediate stoppage of these ascending heated currents with any flying cinders or burning brands that might carry destruction (in a dry, but not when humidity exists in the, atmosphere) to other portions of the city and start one or more fires in otherplaces. The stoppage of these currents by cooling lowers the temperature, and the danger from radiation that existed is correspondinglyditninished, as the temperature is decreased and the rate of combustion thereby checked. This is done not by striking the burning materials directly. A jet of this kind and size, under the conditions mentioned, and a great many mors can be named, would be far more effective in every respect than sixty-four quarter-inch jets possible to be thrown from the manual and stfam fire engines in Loudon directed directly at the seat of combustion, Another error: The editor of The London Fireman tells the firemen of America how to put out a fire in a closet or room and the way the English firemen do it. Now, I dare say, there is not a boy of average intelligence in any city or town or village in this country with the .hand-pump and quartetinch jet who could not do as good service in a closet or room as it is described how England’s firemen do at such conflagrations. I quote again : “Nothing is more certain than the fact that no two fires of any magnitude are exactly alike in all particulars, and it necessarily follows that no single method can be followed in subduing them.” The best authorities (not Captain Shaw) of England assert that all heat is of the same kind, and if the editor had not been misinformed on the subject he would not write anything like that which is quoted above, for the sufficient reason that heat can be estimated and measured by well-known methods, and the quantity and intensity generated at any fire, even in a closet or a room, )n one or more buildings, or in an entire city, when certain conditions are given, such as exist at fires. I think the time is coming when, for every building of any magnitude, or blocks of buildings, the heat it is possible for one or all to generate in any given time or under most any circumstances will all be laid down beforehand, and firemen or companies arriving at the scene of a fire will have a given amount of work to do, not as what this one or that one thinks ought to be done, but with the means at their disposal science will show to a certainty whether or not they have done the work it was possible to do, with the resources at their disposal , in the extinguishment of all classes of fires under the known conditions.

It matters not how far others may have been behind in original research and discoveries; it will suffice to say that the American firemen have made full use of them, and they have not been excelled or equaled by any o their profession on earth so far as devotion or efficiency are concerned. Have England’s firemen 4one as much? Whatever of shortcomings there have been in the past and present among American firemen, is due not to want of discretion and devotion, but the mutations in office for political reasons. In a word, when taking into view the extinguishment of fires in general, and special ones in particular, American firemen believe adequate knowledge of nature’s laws to be necessary for the proper understanding of their phenomena ; that the study of these laws will bring to light many new relations, will give new ideas and will create for the brain the true guiding principles, by means of which firemen can foretell to a certainty different conditions and effects which may exist or can possibly exist at any time or under any circumstances, aud consequently be able to seize at a glance all the salient points at a large or small fire. They believe in tvhat a great philosopher, whose name is associated with immortal discoveries, said to an audience who believed in practical guessing, “ Bear in mind, gentlemen, that in questions of science, the authority of a thousand is not worth the humble reasoning of a single individual.” These words were spoken over two centuries ago byGalileo, and are as true now as they were then. Their value in the knowledge of science, as far as it applies to fire extinguishment, should not be overlooked by any one who wishes to train his mind to understand what is best to do at all classes of fires that firemen are called upon to extinguish.

I think the fireman of the future will be required to be thoroughly instructed in applied chemistry and physics, coupled with such athletic training as will develop his best powers mentally and physically. If this is not the case now, it is not because it ought not to be. The American firemen are constantly improving in that direction. I think all firemen should be educat’ d men, educated to a special branch of work, and thereby enabled to do it with less friction to themselves and the apparatus they have to manage. Such men would be infinitely superior to firemen whose knowledge is gained from mere practical experience, and who act from mere guess-work in sudden emergencies, and who are unaware of the reasons for the many apparently mysterious and unaccountable (at least to them, but not to scientists) things encountered in their work at fires.

Now, 1 asset! without hesitation that if the fire service is ever to be elevated to’the dignity of a profession, it never can be done from guessing experience (which Captain Shaw thinks all-sufficient), and surely no profession could be nobler or more elovating to the character than that which saves the lives and property of otherwise helpless citizens. Such a fire brigade of trained and educated men will have a fundamental conception of their business in all its branches, and would consequently always be able to do the best work possible under the circumstances, and even’ though far from the source of authority, by their superior training and mental agility be able to execute the plan of their chief, should sudden emergencies arise, just as lie would do if he were immediately at hand when the changed conditions arose and which do arise at fires. With such a force large fires would be next to impossible, and the losses from all fires reduced to a minimum.

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