It has been proposed to make the branch pipes, or | at the top of which is a hooked frame for catching a portion of them, proceeding from a reservoir of into the window-sill. In order to raise these hooks this kind, of fusible metal, so that, on the first breaking up to the window-sill, the rounds fit together so as out of a fire, the pipes may melt and discharge water. to form a pole, each round being formed with a proThis, however, would be of very little use, unless the jecting pin at one end, and a socket at the other; so fire happened to break out in so convenient a situation that, by fitting the pin of one round into the socket as to receive the jet of water directly upon it. of the previous round, the hooks are gradually raised until they catch the window sill, a single jerk or pull at the lower end then disconnects the staves from one another, and they fall into their places as rounds of the ladder, while at the same moment the rope sides become distended. Gregory's rope-ladder escape is supported on the window-sill or parapet by a hook composed of two sides, or arms, bent so as to resemble the external figure of the human ear, and hence called an ear-hook: the two sides are held together by three horizontal iron rails, the rope ladder is attached to the hook, and a sliding cradle is also arranged, the rope by which the cradle is worked passing over the central bar of the hook.

We may here also refer to Mr. Rutter's ingenious fire-alarum. An alarum apparatus is placed in the sleeping-room of the master, overseer, or watchman, and a galvanic battery in some other convenient apartment. A thermometer is also placed in every one of the apartments and passages of the house or building, and a double series of copper wires so laid throughout the premises, that on a given rise of any one of the thermometers, it shall immediately put the wires in communication with the battery and alarum apparatus, and so bring the latter into action. The thermometers are so constructed that metallic contact is formed, by means of platinum wires, with the separated parts of the copper wires leading from and to the battery, but in such a manner, that until the thermometers are acted on by a certain amount of heat, so as to cause the expansion of the air or other elastic substance within them, the current of electricity cannot pass from one part of the copper wire to the other; but as soon as this heat is applied, the mercury in the thermometers produces a continuous metallic circuit, and an electrical current will pass. In short, each thermometer, in its ordinary condition, interrupts the electrical current; and only in cases where great heat is produced near the instrument is the circuit closed, and the alarum apparatus set off. The alarum may be similar to that described under ELECTRIC TELEGRAPH, Fig. 817.

Among the simplest forms of portable fire-escape is a good strong rope, with a hook or loop at the end, by which it may be fastened to a bed-post, so as to enable an active person to descend, a partial footing being found in the inequalities of the wall. The descent is greatly facilitated by having the rope knotted at intervals of about a foot, the knots enabling the hand to grasp the rope securely. A common bedcord is usually strong enough to support the weight of a stout man; a quarter-inch rope will readily support 2 cwt. or three times that quantity if new and good. By attaching a sack to the end, and passing the rope once or twice round a bed-post, women and children may be lowered into the street. In the Great Exhibition were two or three forms of fireWe come now to the second part of our subject, escape adapted to the bed-room; in one form a wirewhich leads us to notice a few of the innumerable rope was coiled up upon a drum contained within an contrivances invented for the purpose of saving life ordinary dressing-table, a handle attached to the axis and property from fire. The most obvious forms of of the drum allowing the rope to be gradually let FIRE-ESCAPE are ladders. These are provided by down or wound up. In another form a strong staple many parishes in London, and are hung up horizon- is attached to the window-sill for holding a pulley, tally under a wooden cover by the side of the church. | the rope of which has a small wooden seat or cradle They are made of different lengths, to reach a first, attached to it, so that a person might let himself second, third, or fourth story. The largest kinds down with a second person in his lap merely by are sometimes furnished with guides, or hand rails, holding the rope, and allowing it to pass with reguand also with contrivances for raising them; one of lated speed through his hands. By the same appawhich is a short conical iron tube, jointed to one of ratus he could also ascend to the bed-room in order the upper rounds of the ladder; a long pole fixes into to rescue another individual. When not in use, the this tube, and affords great facility in raising the pulley with its rope and cradle may be kept under ladder. Another form of ladder, already noticed, the bed, or in the dressing-table. Many of the portand to be recommended for its portability and con-able fire-escapes conveyed to, not kept in the burning venience, consists of short lengths, 8 or 9 feet cach, fitting into each other to any required length, by a strong simple joint, in the same way as scalingladders. In Gregory's ladders the two parts or lengths are made to slide one upon the other, and can be sustained at any required elevation: a cradle is attached for the rescue of timid or infirm persons. Wire chain ladders, and rope ladders with wooden steps, have been arranged in a variety of forms as fire-escapes. One of the most ingenious is Adam Young's. This is a rope ladder with wooden rounds,

house, have been useless on account of the difficulty of establishing a communication with the persons in danger. This, however, may be effected by means of rods 6 or 8 feet long, connected either by fishingrod, or bayonet joints, or by screws. In Edinburgh the firemen use a cross-bow, and a three-ounce leaden bullet attached to a cord 130 feet long. The bullet and cord are thrown over the house by the crossbow: to this cord a stronger one is attached, and drawn over the house by the former, and so on, until a chain ladder or escape is elevated.

In 1775 Mr. Hartley's method of rendering houses fire proof, was encouraged both by a patent and a parliamentary grant. Thin iron plates were nailed to the top of the joists, the edges of the sides and ends being lapped over, folded close, and hammered together. It was proposed to protect partitions, stairs, and floors in the same manner. The plates were so thin as to allow the floor to be nailed to the joists in the usual manner, and to prevent the plates from rusting, they were varnished with oil and turpentine. This method did not survive its inventor, nor was it likely to have been very successful, for when it is considered that iron is a combustible requiring only a higher temperature than wood for its destruction, we cannot suppose that any great amount of security is to be obtained from thin iron plates covering massive timber framing.

Of the larger kinds of portable fire-escapes, the | substance which would render it less inflammable, or most efficient is the carriage ladder. In 1809 Mr. to reject combustible substances altogether in house John Davies submitted to the Society of Arts a fire- building. escape consisting of 3 ladders connected to, and sliding upon each other by means of ropes worked by a small windlass. A second windlass raised and lowered a cradle supported by ropes passing over pulleys at the top of the uppermost ladder. This machine was mounted upon a low four-wheeled truck, drawn by a horse, or by 6 men. This escape was improved by Mr. Gregory, who used 3 ladders sliding on each other, which, when lowered, were balanced horizontally upon a convenient frame, mounted on a light four-wheeled carriage, so as to be capable of being run under low gateways, &c. The ladders being brought into the vertical position, or nearly so, are raised by a small windlass in front of the machine to any required height between 10 and 40 feet; the ladders are then inclined towards the window, upon the sill of which the top may be made to rest. A greater elevation than 40 feet may be obtained by means of joints, to be carried up and fixed at the top. A cradle is also used with this machine for the benefit of those who cannot descend ladders.

Our limits will not allow us to devote more space to the description of fire-escapes. We are conscious of having omitted many meritorious forms; but the reader who is desirous of studying the subject is referred to Mr. Baddeley's excellent article in Hebert's "Engineer's and Mechanic's Encyclopædia," vol. i. 1838, to the volumes of the Mechanic's Magazine since that date, and also, to the Transactions of the Society of Arts. People are generally indifferent to this subject until danger actually threatens; but it would be at least prudent that the occupant of every bed-room should ascertain what are the facilities for ascending to the roof, and passing to that of his neighbour. In detached houses internal means of escaping through the windows ought to be provided, but, as Mr. Baddeley remarks, "people rather choose to trust to the chance of obtaining external aid." If this should not be afforded in time, "egress can sometimes be made at the top of a house, either by a door, or by an opening made in the roof with a poker for the purpose. Sheets and blankets tied together, and fastened to the bed-post, or the bedcords attached in the same way, afford the means of descending the feather-bed, &c. thrown out, serve to break the fall when jumping from the window, as the last alternative. With a little contrivance women and children may be lowered by means of the bedclothes. Upon these occasions all depends upon the persons in danger retaining so much presence of mind, as will enable them to avail themselves of the best means in their power: and it often happens that pressing danger develops a great deal more ingenuity and intrepidity in individuals, than they have previously taken credit for."

The third part of our subject relates to the prevention of fires. The methods proposed for accomplishing this desirable end are, to make houses fire-proof either by coating the timber with some

The Earl of Stanhope, among his numerous mechanical contrivances, had a method of fire-proofing which consisted in the use of a non-combustible material, with, among, and between the timbers used in the frame-work of a house. His methods are described under the heads under-flooring, extra-lathing, and inter-securing. Under-flooring is either single or double. In single under flooring a common strong lath of oak, or fir, about 4 inch thick, is nailed against each side of every joist, and of every main timber supporting the floor which is to be secured. Other similar laths are then to be nailed along the whole length of the joists, with their ends butting against each other.

The top of each of these laths, or fillets, ought to be 1 inch below the top of the joists, or timbers, against which they are nailed, so as to form a small ledge on either side of the joists. These fillets are to be well bedded in a rough plaster, so as to leave no interval between them and the joists, and the plaster is to be spread on the tops of all the fillets, and along the sides of that part of the joists between the top of the fillets and the upper edge of the joists. In order to fill up the intervals between the joists that support the floor, short pieces of common laths, whose length is equal to the width of these intervals, should be laid in the contrary direction to the joists, and close together in a row so as to be in contact; their ends must rest upon the fillets, and they ought to be well bedded in the rough plaster, but not fastened with nails. They must then be covered with one thick coat of the rough plaster, which is to be spread over them to the levels of the tops of the joists, and in a day or two this plaster should be trowelled over close to the side of the joists, without covering the tops of the joists with it.

In double-flooring the fillets and short pieces of laths are applied as above directed; but the coat of rough plaster ought to be little more than half as thick, and while being laid on, some more of the short pieces of laths must be placed in the intervals between the joists upon the first coat, and be dipped

deep in it. They should be laid as close as possible | wall, the ends being dove-tailed to form a sufficient

construction. It has been proposed to make the timber itself indestructible by fire, for which purpose Mr. Payne, whose wood-preserving process is well known, has patented a method for rendering timber fire-proof by means of a solution of sulphuret of barium or calcium. The wood or other vegetable matter is put into an air-tight vessel, from which the air is driven out by means of steam: the steam is condensed by the injection of the solution of the sulphuret, and by the application of cold water to the outside of the vessel. A partial vacuum being thus obtained, the solution is allowed to flow into the vessel from the reservoir containing it through a pipe furnished with a stopcock. The stop-cock is then closed, and an air-pump connected with the vessel is worked until as perfect a vacuum as possible is obtained within the vessel. The cock is again opened so as to allow the solution to fill the vessel nearly. It is then shut, and by means of a force-pump a further quantity of solution is introduced, until the pressure on the interior of the vessel amounts to from 110 to 140 lbs. on the square inch. This pressure is maintained for an hour, and the solution is then drawn off. The vegetable matter is next impregnated in a similar manner with an acid, or a solution of some substance, such as sulphate of iron, which will unite with the barium or calcium and set the sulphur free. When the vegetable matter is to be impregnated with a large quantity of solid matter, it should be dried between the application of the two solutions.

The following general directions, for the construc- | proof without abolishing the use of timber in their tion of fire-proof houses of small size, are given by Mr. Loudon, in his "Cyclopædia of Cottage, Farm, and Villa Architecture" (London. 1833-1842). The floors may be formed of flat tiles and cement, and covered with ornamental tiles; or flooring may be made of composition, and polished in imitation of scagliola or artificial marble. The roofs may be made flat, and covered with common cement, and the outer walls of the building may be tied together in all directions by wrought-iron rods made fast to stone bond, as broad as the wall is thick, the stones cramped or dovetailed together, and carried completely round the walls, about the level of the centre of each floor. The netting or lattice-work of iron rods connected with this chain of stone bond being thickly imbedded in cement, and cased with strata of flat tiles, would be kept from extremes of temperature throughout the year; so that the difference in their contraction and expansion during summer and winter would be of no practical importance. Every floor of a house thus formed would be in effect a single flagstone, and, as the iron rods would be prevented from oxidising, it would probably last for ages. It is easy to conceive the skeleton of an entire house thus constructed; the perpendicular supports being brick or stone piers, 3, 4, or 6 feet apart; the horizontal bonds on these supports of flagstone, of the width of the intended thickness of the walls or partitions, and all the horizontalfloors or vertical panels of iron rods and wires covered on one or both sides with plain tiles coated with cement. Even the staircases might be so constructed and covered. In the case of the floors of rooms, square or nearly so, there might be circles of thin flat castiron laid on the horizontal rods, and made fast to them, which would serve as struts; and oblong rooms might have two or more cast-iron circles, or ovals, with plates of cast-iron in the direction of their short diameters, to serve the same purpose. The outer walls might have double panels of wrought-iron rods and wires, with intervals between, so as to form hollow walls; so that houses constructed in this manner might be rendered equally impermeable by cold or heat as those with thick walls, or with hollow walls of masonry. There would be no objection to houses of this description having all the doors and windows framed of timber, provided the panels and astragals were filled in with iron. As the iron rods and wires need not be of great diameter, (perhaps, in ordinary cases, of half an inch for the rods, and one-eighth of an inch for the wires, and half an inch in thickness with 3 inches in breadth for the cast-iron circles,) the expense even for the smallest house would not be an insuperable objection. Were the attention of the legislature turned to this subject, with the view of protecting those who at present cannot protect themselves, we mean dwellers in town houses of the commoner kinds, the Government would probably direct experiments to be made so as to bring this mode of construction, or some similar mode, to a degree of perfection which would soon render it general.

Attempts have been made to render houses fire

Without entering into any further details at present respecting the construction of fire-proof buildings, or stopping to point out the various methods in which iron joists and girders have been and are being extensively employed in large structures, we conclude by calling attention to a statement made about three years ago, by Mr. Braidwood, on the subject of fire-proof buildings, to the Institution of Civil Engineers. He exhibited a collection of specimens of cast-iron which had been used in the construction of buildings destroyed by fire, which showed that occasionally the temperature in the conflagration of large buildings rose almost to the melting-point of cast-iron. It was also stated that, even in a small fire, beams and columns of castiron would be so affected by the heat and jets of water upon them, that they would probably be destroyed, and sometimes cause great loss of life; as, in many the so-called fire-proof warehouses of London, a number of persons employed on the premises slept in the upper floors, and if the lower beams gave way, the whole would be dragged down suddenly; whereas, timber beams resisted fire some time, and allowed time for the inmates to escape. The firemen, also, were liable to more danger from the same circumstance, as the only chance of extinguishing fires was to send them into the buildings with the branches and waterhose; but where the danger was so evident, the men were forbidden to enter, and their efforts were limited to preventing the fire from spreading. The expansion of the iron beams at high temperatures, and their sudden contraction on the application of cold water,

of

caused a derangement of the brick-work: the mortar, | added to the cinders when once they are lighted, but