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them to be to a large extent preventible, that I have ventured to bring the subject of water supply for fire extinction before you.
In the remarks which I am about to make, I purpose to refer largely to the case of this metropolis as being likely to add additional interest to the general subject, and because the reasoning which applies to this will apply in a greater or less degree to all other similar cases.
It may be useful at once to define what are the requirements necessary to be fulfilled in a water supply for fire extinction purposes.
In order to reduce, as far as possible, the destruction of life and property by fire, the fire extinguishing service should have water
(1.) In copious supply.
In nearly all cities the water supply has been introduced and distributed without reference to the fulfilment of these conditions. The quantity of water required for the extinction of fires is so infinitesimal as compared with the quantity required for all other purposes, that, except where the conditions have been naturally favourable, the water service is devoid of some at least of the qualities necessary to fit it for fire purposes. The result, in such cases, has been that mechanical contrivances have had to be provided to make good whatever deficiencies existed in the supplies, and dwellers in cities have become familiar with fire-plugs and fire-engines.
There are, however, some cities in this country where, the conditions having been favourable, the authorities having control of the water supplies have availed themselves wisely of Nature's gifts.
The most notable instances are those of Glasgow, Dublin, Liverpool, and Manchester. In all these cases the water supply is almost entirely by gravitation, and the result is that over the greater and most important parts of the cities there is a good pressure and a copious supply of water, which has been made easily accessible by the introduction of numerous hydrants in close proximity. Here, then, we have, as nearly as may be, in four of the most important cities of the United Kingdom, a fulfilment of the necessary conditions of water supply for fire extinction.
An ordinary hydrant may be shortly described as a stop-cock on a water-pipe or main, to which hose may be attached for fire extinction, or other purposes. If for fire extinction, without the intervention of a fire-engine, the hose will, at its other end, be provided with a branch and nozzle. Upon opening the stop-cock, the water from the main, or pipe, will issue from the nozzle as a jet. The height of the jet will depend upon the pressure in the main, the quantity of water available, the length of hose employed, and the size and shape of the nozzle.
A fire-plug is a wooden plug driven tightly into a socket or opening in a water-pipe under the road. When water is required for fire extinction the plug is withdrawn, and the water issues from the opening, either into the street, where it is usually received by a portable tank, or into a standpipe inserted in place of a plug. It is obvious that plugs cannot be used where the supply is constant with a good pressure, and they have not been placed upon the constantly charged mains (the best existing supply for fire extinction) in the metropolis. Several forms of hydrants, and a fire-plug and stand-pipe, may be seen in the Water Companies' Pavilion in the Exhibition.
In order to obtain a good jet from a hydrant, it is necessary that the pressure of water at the hydrant, while flowing, should be about 65 lbs. per square inch. This will provide for overcoming the friction of the water in passing through an average length of hose, and will give a jet about 80 feet high from an inch nozzle. From the elaborate reports of the chief officer of the Dublin Fire Brigade, which he has kindly furnished to me, it appears that all the fires in Dublin, except those extinguished by small hand pumps, are put out by jets direct from the hydrants, and that the prevailing pressure is about 60 lbs. per square inch.
So much has been written and said about hydrants, and the advantages to be derived from their use, during the last twenty years, that it is hardly necessary for me to discuss their merits as compared with fire-plugs. It is generally conceded that in all cases, whatever the water supply may be, whether constant or intermittent, high pressure or low, hydrants are superior to plugs as a means of letting the water out of the pipes. But it has been contended that so long as it is merely a question as between hydrants and plugs, the advantages of the former over the latter are not sufficiently great to justify any large expenditure upon them. When, however, the question becomes one as between hydrants and fire-engines, a wider view becomes necessary. Hydrants with a constant and copious supply, and good pressure of water, are recognised as being incomparably better agents for extinguishing fires than fire-engines, and the result of the introduction of hydrants into Manchester may be given in illustration. Mr. Bateman, the eminent engineer of the Manchester Waterworks, has stated publicly on more than one occasion, that the introduction of hydrants with a good pressure of water has resulted in a reduction of the losses from fire in Manchester to a small fraction (viz., oneseventh) of what they were before the introduction of the hydrants. And according to the report of Captain Tozer, the superintendent of the Manchester Fire Brigade, the amount of property destroyed has only averaged 4:3 per cent. of that at risk during the last ten years, while it will be seen presently that in places having no efficient hydrant services the losses are many times greater.
In Liverpool, the fire brigade is a branch of the police. The water supply is mainly by gravitation from reservoirs (from 400 to 600 feet above the low parts of the town), and there are numerous hydrants. There are 3 steam and 14 manual fire-engines. The population in 1881 was 548,650, and the area is 8: square miles. Of the 180 firemen, 170 do regular police duty. The average annual cost of the brigade for the three years 1880, 1881, and 1882, was £5325, or £9 145. per 1000 of the population. The average annual number of fires in the same period was 219, but the loss by fire was not ascertained.
In Glasgow, there is a good supply of water by gravitation; there are about 5000 hydrants, and the majority of the fires are extinguished direct from the mains. There are 3 steam and 17 manual fire-engines. The 66 officers and firemen are supplemented by an auxiliary force of 52 policemen. The area of the city is 9} square miles, and the population in 1881 was 510,816. The cost of the brigade to the ratepayers in 1882 was £ 5266, or £10 6s. per 1000 inhabitants; while the annual average loss from fire in the same period was £110,000, or about £215 per 1000 of the population.
In Manchester, the supply is also by gravitation from reservoirs at a considerable elevation (200 feet to 600 feet above the Exchange), and there is a constant high pressure supply. There are about 17,000 hydrants in the city and suburbs. Two steam and 5 manual fire-engines are retained, but are seldom used. The population in 1881 was 341,500. The area of the city is 6 square miles, but the fire brigade extend their operations beyond the city. There are sixteen stations, and the average annual cost to the ratepayers for the fire brigade during the three years 1880, 1881, and 1882, was £ 3547, or equal to £10 8s. per 1000 of the population. The average estimated annual value of property destroyed in those three years was about £80,000, or about £235 per 1000 of the population.
In Dublin, the supply of water is again by gravitation, and the pressure varies from about 40 lbs. to 80 lbs., being generally 60 lbs. when the water is flowing through the hydrants. There are numerous hydrants, and though there are 2 steam and 3 manual engines, they do not appear to have been used in the three years (1880-1882), within the city. The brigade consists of 32 officers and men. The population in 1881 was 249,602, and the area of the city is 6 square miles, but the operations of the brigade are not confined to that area. The average annual cost of the brigade for expenses and wages for the three years in question was £ 3286, or about £13 35. per 1000 of the population. The estimated value of property destroyed averaged £ 31,144 per annum, or about £125 per 1000 of the population.
In Birmingham, the whole of the water supply is pumped, therein differing from the cases already referred to; but a system of fire hydrants has been recently introduced. The population (average of 1882 and 1883) is 411,690, and the area 13 square miles. The fire brigade consists of 27 officers and men, and there are 2 stations and 8 police stations, with apparatus. One steam and 5 manual fires-engines are retained, none of which were used for fire extinction in 1882, and engines were used twice only in 1883. The total water supply is 114 million gallons daily, with a pressure of 40 lbs. to 60 lbs. per square inch. The average annual cost of the fire brigade to the ratepayers during 1882 and 1883 was £ 3250, or £7 18s. per 1000 of the population, while the average annual loss in the two years was £ 10,931, or £ 26 115. 8d. per 1000 of the population, and this loss was equivalent to 3 per cent. only of the value of the property“ at risk.”
Having now described the operations, and their results in cities having efficient hydrant services, I propose to direct attention to some of the more important of the cities having no such services, and more particularly to New York and London.
In New York, the water supply is very copious, but it has not sufficient pressure for fire purposes without the intervention of fire engines. Hydrants have, to some extent, been introduced, and it is stated with benefit, as they permit more speedy access to, and prevent waste of, the water. The total supply is, according to the report of the fire department, about 100 million gallons daily ; the population in 1880 was 1,206,300, and in 1881 probably 1,240,000. The area served by the fire brigade is about 39
VOL. VIII.-H. C.