348 Steam Fire-Engine. [Book III. "E, a cylindrical box attached to the top of the steam chamber, containing a conical steam valve e, and also safety valve e'. e' screw with handle connected to the steam valve, for admitting or shutting off the steam. e'"' induction pipe, for conveying the steam to F, the steam cylinder, provided with steam passages and slide valve of the usual construction, and secured to the carriage frame in the same manner as the force pump. f Eduction pipe, for carrying off the steam into the atmosphere. f' Piston, provided with metallic packing, on Barton's plan. ƒ", Piston rod of steel, attached to the piston rod of the force pump by means of G. a crosshead of wrought iron, into which both piston rods are inserted and secured by keys. g, Tappet rod attached to the crosshead, for moving the slide valve of the steam cylinder by means of nuts g', g', which may be placed at any position on the tappet rod. H. Spindle of wrought iron, working in two bearings attached to the cover of the steam cylinder, the one end thereof having fixed to it, h a lever, moved or struck ultimately by the nuts g', g'. h' a lever, fixed to the middle part of the spindle H, for moving the steam valve rod. I. Force pump for supplying the boiler, constructed with spindle valves on the ordinary plan; the suction pipe thereof to communicate with the valve chamber of the water cylinder, and the delivering pipe to be connected to the horizontal part of the boiler. i, Plunger of force pump, to be made of gun metal or copper, and attached to the crosshead G. J. Blowing apparatus, consisting of a square wooden box, with paneled sides, in which is made to work a square piston j, made of wood, joined to the sides of said box by leather. j', Circular holes or openings through the sides, for admitting atmospheric air into the box; these holes being covered on the inside by pieces of leather or India rubber cloth to act as valves. j', are similar holes through the top of the box, for passing off the air at each stroke of the piston, into K. Receiver or regulator, which has a movable top k, made of wood, joined by leather to the upper part of the box; a thin sheet of lead to be attached thereto, for keeping up a certain compression of air in the regulator. k', Box or passage made of sheet iron, attached to the blowing apparatus, and having an open communication with the regulator at k": to this passage is connected a conducting pipe, as marked by dotted lines in No. 156, for conveying the air from the receiver into the ash pan, under the furnace of the boiler at k""; this conducting pipe passes along the inside of the carriage frame on either side. L, L. Two parallel iron rods, to which the piston of the blowing apparatus is attached: these rods work through guide brasses 1, 1, and they may be attached to the crosshead G, by keys at ', '. The holes at the ends of the crosshead for admitting these rods are sufficiently large to allow a free movement whenever it is desirable to work the blowing apparatus independently of the engine. M. Spindle of wrought iron, placed transversely, and working in two bearings fixed under the carriage frame: to this spindle are fixed two crank levers m, m, which by means of two connecting rods m' m', give motion to the piston rods L, L, by inserting the hooks m", m", into the eyes at the ends of the said piston rods. N. Crank lever, fixed at the end of spindle M, which by means of P. Connecting rod, will communicate motion to the blowing apparatus, whenever the carriage is in motion, and the above parts duly connected. Chap. 8.] Fire Escapes. 349 "A pin n is fixed in lever N, placed at such distance from the centre of spindle M, that it will fit the hole n' of the lever shown in No. 159, whilst n" receives the end of the spindle M. Whenever the blowing apparatus is to be worked by the engine or by manual force, the connecting rod P should be detached by means of the lock at p. The carriage frame should be made of oak, and plated with iron all over the outside and top; the top plate to have small recesses, to meet the brackets of the cylinders, as shown in the drawing. The lock of the carriage, axles, and springs to be made as usual, only differing by having the large springs suspended below the axle. The carriage wheels to be constructed on the suspension principle; spokes and rim to be made of wrought iron, and very light. The principal object of a steam fire-engine being that of not depending on the power or diligence of a large number of men, one or two horses should always be kept in an adjoining stable for its transportation. The fire grate and flues should be kept very clean, with dry shavings, wood and coke, carefully laid in the furnace ready for ignition; and a torch should always be at hand to ignite the fuel at a moment's notice. To this fireengine establishment the word of fire should be given, without intermediate orders: the horses being put to, the rod attached connecting the carriage wheel to the bellows, and the fuel ignited, the engine may on all ordinary occasions be at its destination, and in full operation in ten minutes." Attempts to supersede fire-engines were formerly common. Zachary Greyl is said to be the first who, in modern times, devised a substitute. This consisted of a close wooden vessel or barrel, containing a considerable quantity of water, and in the centre a small iron or tin case full of gunpowder: from this case a tube was continued through the side or head of the barrel, and was filled with a composition that readily ignited. When a room was on fire, one of these machines was thrown or conveyed into it, and the powder exploding dispersed the water in the outer case in every direction, and instantly extinguished the flames although raging with violence a moment before. In 1723, Godfrey, an English chemist, copied this device, and impregnated the water with an "antiphlogistic" substance. He named his machines "water bombs." In the year 1734, the States of Sweden offered a premium of twenty thousand crowns for the best invention of stopping the progress of fires; upon which M. Fuches, a German chemist, introduced an apparatus of the same kind. Similar devices have been brought forward in more recent days; but after making a noise for a time, they have passed into oblivion. (See London Magazine for 1760 and 1761.) Among the devices of modern times for securing buildings from fire, may be mentioned the plan of Dr. Hales, of covering the floors with a layer of earth; and that adopted by Harley in 1775, of nailing over joists, floors, stairs, partitions, &c. sheet iron or tin plate. To increase the effect of fire-engines, the author of this work devised in 1817, and put in practice at Paterson, New Jersey, in 1820, the plan of fixing perforated copper pipes over or along the ceilings of each floor of a factory or other buildings, and connecting them with others on the outside, or at a short distance from the walls, so that the hose of a fire-engine could be readily united by screws; but the plan had been previously developed by Sir W. Congreve. It has recently been brought before the public as a new invention. Of the numerous Fire Escapes that have been brought forward in modern times, the greater part are such as were employed by the ancients to scale walls and to enter fortresses, &c. in times of war. It is indeed obvious 350 Courre Feu. [Book III. that the same devices by which persons entered buildings, would also answer the purpose of escaping from them: and as the utmost ingenuity of the ancients was exercised in devising means to accomplish the one, it was exceedingly natural that modern inventors should hit upon similar contrivances to effect the other. In the cuts to the old German translation of Vegetius, to which we have so often referred, there are ladders of rope and leather, in great variety, with hooks at the ends which when thrown by hand or an engine, were designed to catch hold of the corners and tops of the walls or windows-folding ladders of wood and metal, some consisting of numerous pieces screwed into each other by the person ascending, till he reached the required elevation; others with rollers at their upper ends to facilitate their elevation by rearing them against the front of the walls-baskets or chests containing several persons raised perpendicularly on a movable frame by means of a screw below, that pushed out several hollow frames or tubes contained within each other, like those of a telescope, whose united length reached to the top of the place attacked-sometimes the men were elevated in a basket suspended at the long end of a lever or swape. Several combinations of the lazy tongs, or jointed parallel bars are also figured-one of these moved on a carriage raised a large box containing soldiers, and is identical with a fire escape described in volume xxxi of the Transactions of the London Society of Arts. Anciently the authors of accidental fires were punished in proportion to the degree of negligence that occasioned them; and they were compelled to repair to the extent of their means, the damage done to their neighbors. A law of this kind was instituted by Moses, probably in imitation of a similar one in force among the Egyptians. Other preventive measures consisted in the establishment of watchmen, whose duty it was to arrest thieves and incendiaries, and to give alarm in case of fire. From the earliest days, those who designedly fired buildings were put to death. A very ancient custom which related to the prevention of fires, is still partially kept up in Europe, although the design of its institution is almost forgotten, viz: the ringing of town bells about eight o'clock in the evening, as a signal for the inhabitants to put out their lights, rake together the fire on their hearths, and cover it with an instrument named a curfew; a corruption of couvre feu, and hence the evening peal became known as "the curfew bell." It has been supposed that the custom originated with William the Conqueror, but it prevailed over Europe long before his time, and was a very beneficial one, not only in constantly reminding the people to guard against fire, but indicating to them the usual time of retiring to rest; for neither clocks nor watches were then known, and in the absence of the sun they had no device for measuring time. Alfred the Great, who measured time by candles, ordered the inhabitants of Oxford to cover their fires on the ringing of the bell at carfax every night. The instrument was made of iron or copper. Its general form may be understood by supposing a common cauldron turned upside down and divided perpendicularly through the centre; one half being furnished with a handle riveted to it would be a couvre feu. When used it was placed over the ashes with the open side close to the back of the hearth. (See Dict. Trevoux: Hone's Every Day Book, vol. i. 243, and Shakespeare's Romeo and Juliet, Act iv, scene 4.) In the thirteenth year of Edward I. (A. D. 1285,) an act was passed a In Shakespeare's play of Richard III. act v. scene 3, there is a reference under the name of a watch to these candles. They were marked in sectious, each of which was a certain time in burning, and thus measured the hours during the night or cloudy weather. Chap. 8.] in Ancient Laws respecting Fires. 351 against incendiaries, and night watchmen were ordered to be appointed every town and city. In 1429 another act declared, "If any threaten by casting bills to burn a house, if money be not laid in a certain place, and after do burn the house, such burning shall be adjudged high treason." Beckman says that regulations respecting fires were instituted in Frankfort in 1460. In 1468 straw thatch was forbidden, and in 1474 shingle roofs were prohibited. The first general order respecting fires in Saxony are dated 1521, those for Dresden in 1529, and there is one respecting buildings in Augsburg, dated 1447. The following preamble to an act passed in the 37th year of Henry VIII. by which those found guilty of the crimes enumerated, were to suffer "the pains of death," is interesting in more respects than one. "Where divers and sundry malicious and envious persons, being men of evil perverse dispositions, and seduced by the instigation of the devil, and minding the hurt, undoing and impoverishment of divers of the kings true and faithful subjects, as enemies to the commonwealth of this realm, and as no true and obedient subjects unto the kings majesty, of their malicious and wicked minds, have of late invented and practised a new damnable kind of vice, displeasure and damnifying of the kings true subjects and the commonwealth of this realm, as in secret burning of frames of timber, prepared and made by the owners thereof, ready to be set up and edified for houses: cutting out of heads and dams of pools, motes, stews and several waters: cutting of conduit-heads, or conduit-pipes: burning of wains and carts loaden with coals or other goods: burning of heaps of wood, cut, felled and prepared for making coals: cutting out of beasts tongues: cutting off the ears of the kings subjects: barking of apple trees, pear trees, and other fruit trees; and divers other like kinds of miserable offences, to the great displeasure of Almighty God and of the kings majesty," &c. (Statutes at large.) The crime of arson was rife in old Rome, and it is singular that the mode of punishing those found guilty of it, is among the numerous ancient customs that have been retained by Roman Catholics in their religious institutions. The tunica molesta of the Romans was a garment made of paper, flax, or tow, and smeared with pitch, bitumen or wax, in which incendiaries were burnt; and hence arose the peculiar dress worn by the victims in those horrible, those demoniacal "Acts of faith!" the Auto da Fe, of Italian, Spanish, and Portuguese inquisitions, (to which the scenes in Smithfield and other parts of England may be added,) acts, in which the order of justice was completely reversed-the sufferers being the innocents, and the court and judges the real criminals. 352 Pressure Engines. [Book III. CHAPTER IX. PRESSURE ENGINES: Of limited application-Are modifications of gaining and losing buckets and pumps-Two kinds of pressure engines-Piston pressure engine described by Fludd-Pressure engine from Belidor-Another by Westgarth--Motive pressure engines-These exhibit a novel mode of employing water as a motive agent-Variety of applications of a piston and cylinder-Causes of the ancients being ignorant of the steam engine-Secret of making improvements in the arts-Fulton, Eli Whitney and Arkwright-Pressure engines might have been anticipated, and valuable lessons in Science may be derived from a disordered pump-Archimedes-Heron's Fountain-Portable ones recommended in Flower Gardens and Drawing-rooms, in hot weather-Their invention gave rise to a new class of hydrauli engines Pressure engine at Chemnitz-Another modification of Heron's fountain-Spiral pump of Wirtz. PRESSURE ENGINES, named by the French Machines à colonne d'eau, form an interesting variety of hydraulic devices belonging to the present division of the subject. They consist of working cylinders with valves and pistons, and resemble forcing pumps in their construction, but differ from them in their operation; the pistons not being moved by any external force applied to them through cranks, levers, &c. but by the weight or pressure of a column of water acting directly upon or against them. Pressure engines are not very common, because they are only applicable to particular locations-such as afford a suitable supply of water for the motive column; but wherever refuse, impure, salt or other water can be obtained from a sufficient elevation, such water may be used to raise a quantity of fresh by these machines. In some forms pressure engines appear rather complicated, but when analyzed, the principle of their action and mode of operation will be found extremely simple :-If two buckets, partly filled with water, be suspended and balanced at the ends of a scale beam, and a stream be directed into one of them, that one will preponderate, and consequently the other with its contents will be raised, and to a height equal to the descent of the former; but when it is required to raise water in this manner to an elevation that exceeds the distance through which the descending vessel can fall; then the capacity of the latter is enlarged, and it is suspended nearer to the fulcrum or centre on which the beam turns, as in the gaining and losing bucket, page 66:-It is virtually the same principle that is employed in pressure engines; the difference is principally in the manner of performing the operation. Instead of vessels suspended as above, two solid pistons, moving in cylinders, are attached by rods or chains to the ends of a beam, or to the ends of a cord passed over a pulley, so that the pressure of a longer or heavier column of water resting upon one piston forces it down, and thereby raises the other and with it the lighter or shorter column reposing upon it. By referring to the 16th illustration on page 64, it will be apparent that if a cylinder extended from B to the top of the cistern Z, and a hollow piston like the upper box of an atmospheric pump fitted to work in it were substituted for the bucket B, the effect produced would be much the same as with the two buckets, for the same quantity of water could be raised through the cylinder into the cistern Z, if allowance were made for |