ON BREAKING OPEN HOUSES ON FIRE. Being a novice in the algebraic art, notwithstanding the numerous examples given in Mr. Wallace's excellent little work, I have found it difficult in application; I would therefore esteem it a favour, if either the author or any of your numerous correspondents would favour the public, through the medium of your useful pages, with solutions by the above rule of the following; viz. a3+9x2+4x=1940 +4x=1040 x1 — 9x2+6x-x=1590, in all of which will be found 10; and, 23+3x2+3x=39,303, in which x will be found=33. The publication of this with the answers you may receive, besides benefiting others, may prevent me again appearing in your columns under the title which I am obliged to subscribe myself, I am, Sir, Your obedient servant, Myddleton Square, ON BREAKING OPEN HOUSES WHEN ON FIRE-IRON BRESTSUMMERSAND NEW POLICE. Sir,-In reply to the strictures on the "conduct of the new police in case of fire," contained in your 329th Number, permit me to say that I deny the impropriety of breaking open the doors and lower parts of a house on fire; and that, had the police men been prevented by their instructions from so doing, much evil would inevitably have resulted. As the circumstances attending the occurrence of accidental fires are in almost every case different, so necessarily must be the procedure of those persons whose duty it becomes to endeavour to suppress them. To give definite instructions that this, or that, shall-or shall not be done, in such varying cases as these, would be highly absurd. The Commissioners of the new Police have, therefore, only furnished their men with general and discretionary instructionsthe only method their present arrangements will enable them safely to pursue. I have frequently met with persons taking the same view of the case as your correspondent "J.S.S.;" but such persons have, like him, derived their information on this subject, from the 299 imperfect, and generally incorrect statements of these accidents, furnished by the newspapers, from which no conclusion should be drawn. The only fault is, where, after the doers, &c. have been broken open, good use is not made of the ingress so obtained. If the personal observation of "J.S.S." has ever extended to a case where mischief has resulted from persons breaking open the lower part of a house, when on fire, it must not be attributed to that circumstance, but to the absence of necessary means, or to the proper use of those means, to avail themselves of the opening so made. Opening the lower part of a house admits a supply of fresh air to rush in, which assists the conflagration, and so far is an evil. But, on the contrary, an opening thus made permits the extent, situation, and probable direction of the fire to be correctly ascertained, and also greatly facilitates the steps taken to extinguish it. By it also the inmates may be aroused, assisted, or extricated, and very frequently a considerable portion of their property saved. An entrance having been obtained, the origin of the fire can be frequently ascertained and determined, whether wilful or accidental. On these several accounts, therefore, breaking open is a positive GOOD, and not so reprehensible a practice as many persons imagine. To illustrate the matter by example, permit me to relate the following brief account of one or two fires which have occurred lately, and at which the practice censured by "J. S. S." was resorted to: About three o'clock in the morning of the 17th October last, a fire broke out in Rood-lane, Fenchurch-street. Upon the arrival of the beautiful engine belonging to St. Edmund's parish, (see vol. xi, page 7,) the engineer, L. Rogers, tore down the shutters, and displayed the shop (a carpenter's) one vivid mass of fire, the story-posts and brestsummer just lighting up. The before-named engine was set to work in gallant style; and notwithstanding the highly inflammable nature of the materials on which the fire was preying, consisting of thin deals, boxes, shavings, &c., the whole of the fire in that part of the premises was quickly extinguished, and prevented from entering the dwelling above. This engine not being properly supported by those sooner on the spot, the fire raged for some time, and did considerable damage in the rear of the premises. But the prompt exertions of the firemen of the several insurance offices soon effected 300 DARBYS FIRE AND BURGLARY ALARM. the total suppression of the conflagration. As an eye-witness of the above transaction, I can bear ample testimony to the great advantage obtained in this case by opening the front of the premises. Without it, in fact, a great waste of labour and consequent loss of effect must inevitably have ensued. Again, no longer ago than last Thursday, the 3rd instant, about one o'clock in the morning, a fire was discovered in the old-established patent-medicine warehouse, under the south piazza of the Royal Exchange. The watchmen immediately broke open the premises, and succeeded in putting out the fire. In each of these cases the blame, if any, attaches to the old police; in the following to the new :— At the late serious conflagration at the corner of Well-street and Oxfordstreet, the door was broken open, but from the highly combustible nature of the stock, and from the length of time it had been burning, the fire had attained such a head when discovered, that all efforts to suppress it were for a length of time unavailing. In this case the door was broken open too late to do either good or harm. Not so, however, in the following instance, which occurred on the 24th of November last, at the White Hart public-house, the corner of Portpool-lane and Leather-lane, which was discovered to be on fire by police officer Birbeck, No. 69, E division. Having alarmed the inmates, he burst open the door, and discovered the bar enveloped in flames, the fury of which was greatly increased by the quantity of spirits and other inflammable matter with which that part abounded. Birbeck being reinforced by more of his party, headed by their serjeant, and aided by a plentiful supply of water, they succeeded in extinguishing the fire in about fifteen minutes. While such results as these attend the breaking open the lower part of houses, when on fire, GOD forbid that any instructions should be issued to prevent it. Having always taken considerable interest in these matters, I could fill the whole of this and the next week's Magazine with similar accounts; the above, however, are quite sufficient to support the view I have taken of this subject. The new police have not yet had suffi cient experience to render them so perfect as they promise, and as we may reasonably expect them to be. They are, for the most part, strong, active, and intelligent men; and I hope that by and by they will assume still more and more the character of a FIRE POLICE; and that they will be furnished with the necessary apparatus, of which they are at present destitute, to render their exertions more powerful, and consequently more effectual. Though I am by no means surprised at the opinion entertained by J. S.S." yet I am so that it should be held by him, when I remember it is not yet two years since he proposed, and strongly advocated breaking into houses on fire, aye, even through brick-walls! See vol. ix. pp. 67 and 311. I should be very sorry for your correspondent to suppose that I have combated his idea from any spirit of contradiction. On the contrary, it is only from a conviction-a conviction founded on practical experience-that the view he has taken is erroneous; and that his communication at page 272, if suffered to pass unnoticed, is calculated to seriously injure that cause, of which I am confident he is a well-wisher. With regard to the objection which "J.S.S." has advanced against the use of iron brestsummers, I shall only observe, that although the case he has adduced may, perhaps, be within the bounds of possibility, yet it is so very, very far removed from probability, that I consider any further comment unnecessary. I have, upon a former occasion, urged the necessity that we should possess correct ideas on the all-interesting subject of fire-suppression, and can only now offer the same as an apology for this intrusion on your columns. 1 am, Sir, Yours respectfully, DARBY'S FIRE AND BURGLARY ALARM. Sir, I have read with much pleasure the numerous communications on the subject of "fire-escapes," inserted in your Magazine: but if it is important to have the means of escape, how much more important is it to know, when a fire has taken place in a house, so that persons may have an opportunity of availing themselves of such inventions? I own it is for a double purpose (but, believe me, a pardonable one) that I call the attention of your readers to Darby's patent fire and burglary alarm. It is the invention of an honest, industrious man, who is CONVERSION OF CANALS INTO RAILWAYS. suffering all the ills attendant on the A MECHANIC. [The model of this fire-alarm is left at our office for inspection. It is ingenious and simple, and we hope will meet with the patronage it merits.-EDIT.] CONVERSION OF CANALS INTO RAIL- Sir, In a note at p. 211, of your 301 of mine you have thought worth insertion in your 329th Number. Be that as it may, I cannot but think that if it can be shown that, by a greater power of steam, you can propel a given quantity of heavy goods at a cheaper rate than can be effected by boats drawn by horses, this greater power will be employed, and the canal is left without any advantage whatever over the railway. It may be true, in one point of view, that for some species of heavy goods, a greater speed than two miles "is not wanted," yet the most economical mode of conveyance will certainly be adopted, and in a calculation of expense the consideration of time must by no means be lost sight of. Suppose the same quantity of coals to be drawn by a steam-engine a given distance in 6 hours, as it would take 2 horses to accomplish in 24 hours, moving at the rate of 2 miles an hour; you have on one side to compute the wear and tear of the engine and rails, a few shillings for fuel, and 6 hours' wages of the engine-man-on the other, you have to pay the bargeman and driver their 2 days' wages, providing food for your 2 horses during the same time, or what would be equal to the feed of 8 horses for 6 hours, and it is dispatch alone which makes all this difference. I think also that there are many objections and obstacles to the laying down rail-roads on the sides of canals; for, in the first place, it does not appear likely that canal proprietors generally are at present possessed of strip of land wide enough to form a commodious double railroad upon, especially on that side of the canal not occupied by the towingpath; and what an outlay of money to purchase this! Then, where there are embankments, you must deepen and widen these proportionably-an expensive process! Again, how are you to carry your rails past the bridges? Only, as appears to me (at least in the generality of cases) by building another archway, which, as it will havé its base on the canal bank, and cannot necessarily be carried higher (if as high) as the key-stone of the waterarch, I should doubt would be mostly too low to admit the passage of an 302 METHOD OF MEASURING HEIGHTS AND DISTANCES. engine and waggon. At any rate, the expense would be enormous, and I should think inevitable. On the whole, as you have offered no objection of a scientific kind to my simple suggestion, I cannot but think that we shall see this method of constructing rail-roads upon the beds of canals for the conveyance of all sorts of merchandise, very generally adopted, both to the benefit of the public and the proprietors. I am, yours respectfully, Chelsea, Dec. 3, 1829. NEW AND EASY TO MEASURE DISTANCES OF TAINS, &c. WM. D. R. METHOD BY WHICH Sir,-As the determination of the heights of hills and mountains, with any considerable degree of precision, has ever been regarded as rather a difficult application of the principles of mathematical science, as is evident from the conflicting results regarding the Peak of Teneriffe, and other mountains, as given to the world by many eminent philosophers any method that has for its object the simplification of this process, together with increased precision of result, may not be deemed wholly uninteresting to your numerous and intelligent readers. Should you concur in this opinion, and think the following plan possessed of either of these requisites, you will much oblige, by its early insertion in your far-famed and useful miscellany, Sir, Your most obedient servant, Duncan's Bay Head, Oct. 1, 1829. The plan, or method referred to, is simply as follows:-On a fine, clear, sun-shiny day, observe when the sun's bearing approaches that of the hill whose height you wish to determine. With a surveying-chain, measuringtape, &c., lay off a base-line in the usual manner, (the longer the better, provided the sum of the horizontal angles at the base be not less than 90°,) with as much precision as possible, and as nearly at right angles to the hill as the nature of the ground will permit. Then with a Hadley's sextant, or quadrant, well adjusted at each end of the base, measure the horizontal, or inclined angles, which the hill in question makes with the opposite end of the base-line respectively, and carefully note the results. Taking a mean of two, three, or more observations of each angle, will conduce to still greater accuracy; and is a mode of operation never to be neglected, where the circumstances of the observer will admit. With these angles and the base jointly, the distance of the hill is to be inferred in the ordinary trigonometrical manner; and its correctness will always be directly commensurate with that of the base and horizontal angles. By this time we will suppose that the sun bears directly over the hill under consideration, or, which is the same thing, is on the vertical circle passing through its top. At that end of the base, or point, above which we wish to ascertain the height of the hill, with an artificial horizon of mercury, or of common spring water, well defended from the agitations caused by the wind, take the altitude of the sun's lower limb by reflection; half this angle will be the apparent altitude of that limb above the true horizon. Instantly bring the same limb of the sun directly in contact with the top of the hill, and note the angle; the difference between which and the former, or sun's altitude, will be the true angular altitude of the top of the hill above the place of observation. A mean of two or three observations of this angle, taken within as short a space of time as possible, is always to be preferred to any single observation. Refraction is not taken into account, because of its uncertainty and variableness with regard to hills situated on the verge of the horizon, and because it is not supposed to affect the relative altitudes of the sun and hill, otherwise it might be easily allowed for. Should the hill lie to the northward of the observer, the only difference would be to make use of the back, instead of the fore, observations, the sun being on the opposite side of METHOD OF MEASURING HEIGHTS AND DISTANCES. the vertical circle, intersecting its top. The distance and altitude of the hill being thus obtained, the mode of ascertaining its perpendicular height. must be obvious to the merest tyro in trigonometrical knowledge. If the observer is so near its base, or the hill so lofty, that its image may be seen by reflection from the artificial horizon, then it is evident that its altitude may be taken without the intervention of the sun's altitude at all, and the whole process will thereby become considerably easier. The great, indeed the only advantage of this method over every other with which I am acquainted, is, that by it the angular altitude of a distant hill, .303 or mountain, too low to be seen by re- I shall now conclude with an example illustrative of this method: which example is the actual determination of the height of a small hill and tower in this neighbourhood, on the 25th of September last. |