FORTY YEARS ACQUAINTANCE WITH FIRE MATTERS.

FORTY YEARS’ ACQUAINTANCE WITH FIRE MATTERS.

(Concluded.)

It may be proper to offer some explanation on chemical engines, inasmuch as several years ago I was sharply criticised because I had not given the preference to carbonic acid gas over spray in extinguishing fire. I asked for an explanation of the philosophy of the action of chemical extinguishers, but no answer has ever been given that I know of. Deeming a knowledge of the subject essential to a clear understanding of the art of extinguishing fire, I will say that fires may be extinguished by cold or excluding the air or diluting the air with some neutral substance. As a proof, take a glass fruit jar, put a spoonful of bicarbonate of soda, add to it a wineglassful of suphuric acid ; the acid will unite with the soda and liberate the carbonic acid ; now put into the carbonic acid wh ch oc .upies the upper part of the jar a red-hot piece of iron (a piece of railroad iron will answer); it will remain red-hot some time ; then withdraw it and put it into cold water and it will cool immediately. This shows very clearly that carbonic acid does not Extinguish fire by cooling it. Now put a piece of blazing paper into the carbonic acid and the flames will be extinguished instantly. Tnis does not account or explain the extinguishing power of chemical engines by any means, so I will go further. The carbonic acid in chemical engines is liberated in a close vessel under pressure; the water absorbs several times its volume of gas, and as soon as the stop-cock is opened the water and gas are driven out by the pressure of the gas in the upper part of the tank ; and as soon as the water and gas are outside the tank, the gas begins to expand, and as the velocity of the stream is diminished the expansion of the g.ts becomes greater, and if it has sufficient distance to go it is converted into a fine spray. So the very substance which my critic has requested me to subject to his superior carbonic acid, is the prime factor in extinguishing fire espec ally. Is that so when any considerable amount of .ed-bot charcoal has been found? To get a clearer idea of this subject, let us suppose the nozzle to be three-eighths of an inch in diameter and the surface of fire which the spray strikes to be four inches in diameter ; the covering surface will be one hundred and thirteen times greater than the stream when it left the nozzle. Is there any wonder that the chemical engines have such a high reputation as they have? I do not caie whether a spray is produced by the intervention of chemical agency or by direct mechanical agency. 1 have nothing to do with the invention of chemical engines ; nevertheless, I say they are an excellent auxiliary when properly used at the right time, which is at the early stages of a fire. The tapidity with which they can be brought into action is of very great importance and requiring comparatively little skill in using, but their sphere is limited on account of the life-destroying gas which is the element of their vitality, while a spray derived from water only is perfectly harmless and the best protection from cither diffused or radiant heat that is known. Besides there is no need of stopping to charge up with chemicals and water. The late fire in Illinois, where so many lives were lost, might have been arrested if the building could have been filled with the poisonous gas, hut I don’t intend to advocate any measure that will save a building at the expense of human life. Same time ago there was a statement in the fire papers that one pound of carbonic acid gas was equal to forty pounds of water in fire extinguishment. I think this is probably true, the way water is applied. I hope to have the pleasure of showing those engaged in fighting fire that there is some progress being made in fire matters, and that it depends very much how water is applied as regards its extinguishing powers.

In summing up, I must say that it is only at short and moderate range that the highest percentage of water can be utilized, and then it must be delivered in the condition of fine spray and high pressure. There are two reasons why high pressure is indispensable. It is well known that any missile projected into the air soon falls to the ground ; one cause is the attraction of gravity and the other the resistance of the air, and as a spray of sixteen thousand particles to the cubic inch presents twenty times more surface to the air than a solid stream does, the need of high delivery pressure is apparent. The other reason for using high pressure is not so apparent—it is nquited to overcome the coheson bet ween the panicles of water. If you place a tumbler on a level table and fill it carefully with water, you may see tnat t ie water will stand above ihe line of the tumbler. This is due to the particles of water. If you now place a fine needle carefully on the surface of the water it will float, and if you look close you will see the needle make a furrow where it rests. But the most familiar illustration of the coheson of water are the “drops of water that does adorn the rugged thorn when wet with pearly dew.” It would be an interesting problem to determine how many foot-pounds of power it would require to convert a gallon of water of forty degrees into a spray of two million particles to the cubic inch. As water in the condition of spray cannot be used at all times to the best advantage, it is no reason why it should not be used wherever possible ; and as there are good devices in existence by which the water can be graduated according to the distance from the fire, I can see no reason why there should be such an adhesion to solid streams only. The adoption of Siamese couplings does not seem to have been attended with any great success if we may judge from the amount of fire losses during the past year. High pressure of the pipe means higher pressure at the engine, and when the engine is a consider-able distance from the fiie it is difficult to get the required delivery pressure high enough, as the loss of pressure per hundred feet of hose is about seven per cent. If two engines are in use it will be better to put one near the fire and the other at the water, for it is better to deliver one good spray than either two poor sprays or poor solid streams. As water is what is used for extinguishing fire it is supposed that the more thrown on the fire the better. This is a mistake. If half the water that is generally used was applied with the extra force that would be required to throw the other half, the result would be much better. While I strongly recommend spray where it can reach the fire, it would be foolish to use it where it cannot. Where it is necessary to throw a great distance, a solid stream must be used ; but remember that in so doing we sacrifice quantity of effect to certainly. Where it is necessary to throw a stream at right angles to a brisk wind, a large solid stream may be used with advantage, and in this case only. It requires a very limited knowledge of figures and common sense to perceive that large solid streams cover the least surface, absorb the least heat, generate the least steam, extinguish the least fire and do the most damage with water. Let us now compare a two-inch solid stream with four-inch nozzles and delivering a spray covering twenty square feet of surface, or eighty feet in all. Can any man possessed of common sense fail to see that the spray must have the advantage ? If there is I would like to test the matter with him if opportunity presents. It looks to me that the advocating and resorting to large solid streams is an eflort to accomplish by force what ought to be accomplished by science and skill. I think the burning of the Masonic building in New York is an illustration of the case if the report as to the amount of water thrown (not used) is correct.

It is possible there may be some readers of THE JOURNAL who may wish to know what my idea of the utilization of water is in extinguishing fire. I will tell these that it consists in making water absorb all the heat it can. For instance, if we take a pound of water at forty degrees and so dispose it that it will absorb 172 units of heat, it will bring it up to boiling point ; but if we can expose it in such a manner that it will be converted into steam, 960 units of heat more will be absorbed. It is not claimed that any considerable percentage of water can ever be fully utilized, but it is claimed that it is proper that it should be known in what direction we should direct our energies to produce the best results. Though the extremes between two-inch solid streams and two million panicles to the cubic inch is great, a careful examination of many of our advanetd industries will show that their success depends largely on what I am advocating—that is, mechanical preparation to assist chemical action. The miner grinds or stamps his ores, the tanner grinds his bark, the dyer grinds his dye wares. All these are mechanical operations for the purpose of facilitating and increasing the chemical operation they must undergo. But that which most interests civilized man is the mechanical preparation of his food. Supposing at the late convention in New Orleans, when the delegates were invited to a banquet, on entering the dining hall they had found everything requisite for a firstclass repast with the single exception of bread, and in place of bread a bowl of clean, dry, white wheat placed at the side of every man’s plate with a printed card on it, “ Please to swallow the wheat without chewing.” Would it not have been thought very barbarous treatment ? But how much more so is it than a great many firemen treat fires? No doubt the pre-historic mar, dispensed with the services of both miller and baker, but is that any reason the civilized man should ? Water in some cases will subdue fire no matter how thrown on, but is it any reason why we should persist in applying it in the most primitive manner when appliances are to be had which will perform the work from five to ten times quicker?

I have given a few instructions relating to fire service, but the best method that I can think of is to prove by actual trial whether spray or solid stream is the best. In 1865 a test was made in Hartford at which the spray proved immensely superior. The laws of nature are the same now as then, but the art of extinguishing fire has advanced one hundred per cent. It has long seemed to me that the best place to give instructions to firemen would be at firemen’s conventions. With this idea, and the great inducement* held out by Rochester firemen in 1882, I sent a representative fully prepared, not to tell how to extinguish, but to extinguish actual fire, not with solid streams, but with spray varying from a few thousand up to half a million particles to the cubic inch, but as no facilities were offered no information could be imparted. This State convention will be held in Utica next August; what inducements will be offered to inventors I know not, but this I do know, that the citizens of Utica have it in their power to make the forthcoming convention the most valuable and instructive to firemen that has ever been held in this or any other country.

LITTLE FALLS, N. Y. CHARLES OYSTON.

FORTY YEARS’ ACQUAINTANCE WITH FIRE MATTERS.

FORTY YEARS’ ACQUAINTANCE WITH FIRE MATTERS.

(Continued.)

Few people have have had more opportunities, or perhaps I ought to say experience, than myself in meeting with the prejudices of firemen. Several years ago, in conversation with a brave and energetic fireman, I recommended applying the water in the condition of spray when the fire surface was moderately large and within reach of the spray. His hasty reply was, ” D—n your spray nozzle; at the old furnace fire I struck a beam, the water spattered like h—1, and I had the fire Out In a little while.” This fireman could see very well that his success was due to the spattering, but his prejudice was so much stronger than his reason that he could not sec that the spattering was but an imperfect spray. Some time after this, duty called him to battle with another fire; this was the time when we had no spray nozzles in use. The building was about forty feet front by sixty feet deep. The north end stood in the river, and consequently it had to be fought from the south side. The building was two stories in front and four in the rear; it was a wood-working establishment, and the fire had full possession when the firemen arrived. The water was handy, and three solid streams were quickly pouring into, or, rather, shooting through it, for the north end had many windows so as to throw light on the lathes, and when the streams did not strike a solid body they would pass through the building and a considerable distance into the river also. And here let me ask old observing firemen if a stream of water won’t go through a burning building of this kind quicker than through ordinary air. There are two reasons, I think, why it should : one is that the air is lighter on account of being hotter, and offers less resistance, and the draft is upward, which counteracts gravity. In this case the streams were nearly horizontal. I must now tell that the fireman referred to did not find the beam, nor one like it, that had rendered him so much service at the old furnace, so the water did not “ spatter like h—1,” and consequenty he did not get the fire out in a little while; in fact, he did not get it out at all, for when the morning sun rose there was hardly wood enough left to boil his coffee for breakfast. When the department found they could not save the building they wisely turned their attention to the adjacent buildings, which thejsucceeded in saving. This fireman is a man of full average ability, a builder by trade and well up in his calling; but, as carpentering and joining require no knowledge of chemistry, he does not possess any, and, like thousands of brave firemen, the only way he can see to extinguish fire is by direct mechanical force. Prejudice in this case led to no fatal results; not so in every case. I have said that I visited the Chief when in Chicago ; he was so thoroughly wedded to solid streams that he would not use a spray for anything, though he had them. Thinking he might have got some defective ones, I expressed a wish to see them. He threw open a cupboard door, and there were seven. He handed me one which I found all right ; they were all done up in papers just as they had come from the factory. Now, had this chief done even half as well as Mr. Hill or Mr. Bennett, as well as many others, there would have been a probability of that terrible conflagration being averted, as the buildings where the fire begun were low, which favored the action of spray very much. But the unfortunate gentleman’s knowledge was too limited for the occasion. And here let me ask, in all sincerity, if our firemen are perfectly satisfied that they are in possession of all the knowledge necessary for the full performance of their duties?

I must now turn my attention to a class of men who, I think, are unintentionally guilty of obstructing the progress of the science of fire extinguishment; a class of men who, by their education and superior intelligence, command the confidence of the public to a very great extent. The parties 1 refer to are those engaged in collecting and diffusing intelligence, the reporters and editors of our newspapers, who, in describing fires are very apt to speak of “ masses of flames,” or to say “ the building was one solid body of flame.” These statements coming from such respectable men as the majority of our editors are, our firemen naturally believe them and act accordingly by hurling powerful, solid streams of water, the major part of which is worse than wasted. Now, there is no such thing as “ masses of flames.” What is flame? Let us determine what flame is, then we shall be better able to judge whether it ever exists in masses or not. Go to the gas bracket, turn the gas on, put your finger over the opening and you will feel it; put your nose near it and you will smell it; apply a lighted match to it and you will see it. Why does a lighted match make it visible ? To understand this we must understand what gas is. Gas is principally composed of two elements; the first is carbon or charcoal which, in its uncombined state is always solid; the other element is hydrogen, which is always a gas in its uncombined state. These two elements, when combined, are found in the solid, liquid and gaseous states. When gas is lighted the hydrogen burns first and the carbon is precipitated in the state of very fine dust; this dust is rendered white-hot by the burning hydrogen, and this is what gives us our artificial light. All flame is burning gas, the same substantially as we burn in cur streets.

The next thing is, what is burning? Burning is the union of the oxygen ol the air with one or both of the above-mentioned substances. Street gas or flame Is only about half as heavy as the air, or about half an ounce to the cubic foot, and as flame can only exist when the gas is in immediate contact with the oxygen of the air, we can never have flame more than the fraction of an inch thick. We thus see that the ” masses of flame ” spoken of is only a delusion. That it has the appearance of being solid 1 admit, for it hides whatever is behind it completely. In consequence of flame being so very light it ascends with great rapidity, spreading destruction and very often death; when the source whence it rises cannot be reached it is very difficult to conquer. But after all flame often yields to what would seem very mild treatment. Shut it up where it cannot get air and it dies at once; but as this is very difficult, resort is had to substituting or mixing carbonic acid gas with the air, which is fatal to flame; but it is equally fatal to animal life. Now, what we want is something that will not only destroy flame but will extinguish solid fire also, and that without either destroying or injuring animal life. If I am not mistaken this is a pearl of great price, and so simple and cheap that I am afraid it will be despised because of its plebeian character; and as its great merit depends very much on the manner in which it is applied, ! will now state that a pound of coal requires about ten pounds of air to burn It, and that the amount of air required by any other substance will be in proportion to the amount of heat that it will give out; and as we rarely can prevent the air from rushing in on the burning substance, I propose to use that air by making it carry in enough water to extinguish the fire by dividing the water up into a spray of two million particles to the cubic inch. I have frequently generated a spray that would.float in the atmosphere by the power of one man; and I can see no reason, when aided by steam, why water in this condition cannot be made a valuable auxiliary in extinguishing fire. Remember that ten pounds of air occupy a space of 140 cubic feet. Is not this vehicle large enough to carry enough water to arrest a fire if sent with sufficient rapidity ? If a foot of air takes but half an ounce of water, it would produce nearly a foot of steam. It will probably seem absurd to the champions of great solid streams that I should advocate such a very fine spray, but it is the best method I know of for reaching around corners, angles and curves. As a solid stream travels nearly in a straight line, it may be made to extinguish fire in front of it; but, as most things have two sides to them, we cannot make a stream turn around and hit the opposite side ; but if the air holds the water in suspension and the air goes to the opposite side.it must take the water with it.

One of the difficulties’of extinguishing fires in sash and blind and furniture establishments is the large surface of fire to be met on all sides at once. If anyone knows any better way of extinguishing flame than by fighting it with a spray as fine as circumstances will permit, I should like to know what it is. A very interesting and inexpensive experiment may be tried as follows : fill a soup-plate or similar article with water ; then put a lighted lamp or candle in it and cover it with a glass jar ; in a short time the flame will go out. If we ask the reason, the answer will probably be, “for want of air.” but, as the jar is nearly full of air, the answer cannot be correct. The explanation is this : the composition of our atmosphere consists of two gases, about twenty-three per cent of oxygen and seventy-seven of nitrogen ; these two gases are very dissimilar in their natures ; if our atmosphere were all oxygen, iron and many other metals would burn up about as rapidly as wood does now. On the other hand, if the atmosphere were all nitrogen, not a single thing would burn, so it is owing to the wise admixture of these two gases that we are enabled to live and breathe and have our being. Returning to the glass jar and its contents, we shall have no difficulty in explaining why the light went out. I have said that burning was the uniting of oxygen with either hydrogen or carbon, or both, and in so doing carbonic acid is produced and frees nitrogen ; and, as neither of these substances are supporters of combustion, they destroy the equilibrium of oxygen and nitrogen as established by nature. Nitrogen, steam and carbonic acid may be considered as neutrals, as none of them will either burn or support fire. By looking at the jar, it will be seen that the water is higher inside than out, proving that there is less air inside than there was in the beginning, in consequence of one portion of the oxygen uniting with the carbon, and carbonic acid is produced, a denser substance than air; another portion of the oxygen unites with the hydrogen and forms water. By comparing the space occupied by the water in the jar and that portion occupied by the air and the two neutral gases, it will be seen what a small portion of neutral material it requires when mixed with the air to prevent the existence of flame. Firemen, is it not worth your while, in the early stages of a fire, to try to present some portions of the water in such a condition as will permit it being converted into steam? Try it once; there is nothing like trying.

(To be continued.)