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SAFES
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SAFES , STRONG-ROOMS AND VAULTS. The See also:term " safe," whilst really including any receptacle for the secure custody of valuables provided with a See also:lock or other See also:device intended to prevent any See also:person except the owner or some person authorized by him gaining See also:access thereto, has gradually come to be confined to such receptacles when fitted with a See also:vertical See also:door, as distinguished from a lid, and of such a See also:size that they can be moved into position, by the use of proper appliances, in one piece. Such receptacles, when so large as to require that their parts should be assembled in situ, fall under the term " strong-rooms," or in the See also:case of safe-deposits " vaults," and when constructed with hinged lids, as distinct from doors, under the terms " See also:cash-See also:box," " See also:deed-box " and "See also:coffer." The term " coffer " is probably the most See also:ancient, and in earlier days included, as it still does in See also:France, what are now known as safes.
Although it is practically certain that boxes provided with locks or coffers must have followed closely on the development of locks (q.v.) and been in use in ancient See also:Egypt, yet no examples remain to us of earlier date than the See also:middle ages. The earliest examples extant were constructed of hard See also:wood banded with hammered See also:iron, and subsequent development took See also:place rather on See also:artistic than on See also:practical lines up to the See also:time of the introduction of boxes entirely of iron. On the See also:continent of See also:Europe the iron box was See also:developed to a very high See also:standard of artistic beauty and craftsmanship, but with no real increase of See also:security. Several specimens of these coffers supposed to be of 17th-See also:century workmanship are preserved in the museum at See also:Marlborough See also:House. See also:Cast-iron chests seem to have been made in various parts of See also:Great See also:Britain in the See also:early See also:part of the 19th century, but the use of wrought iron was probably confined to See also:London until 182o, or thereabouts, when the See also:trade spread to See also:Wolverhampton.
Up to this time no See also:attempt had been made to make coffers fireproof, for though a patent for fireproofing had been taken out in 18or by See also:Richard See also:Scott, it does not appear to have been used. In 1834, however, a patent was obtained by See also: The patent he obtained in 1840 contains the following claim: " Constructing, forming, or manufacturing boxes, safes, or other depositories of an See also:outer case of iron or other See also:metal or material, enclosing one, two, or more inner cases, with spaces or See also:chambers between them, containing an absorbent material or See also:composition, such as porous wood, dust of wood, dust of bones, or similarsubstances, in which are distributed vessels, pipes or tubes filled with an alkaline See also:solution or any other liquid or See also:matter evolving See also:steam or moisture, the tubes or vessels bursting or otherwise discharging themselves on the exposure of the box or other depository to heat or fire, into the surrounding absorbent matter, which thus pervaded with moisture and rendered difficult of destruction, protects the inner cases or boxes and their contents." In 1843, See also:Edward Tann, Edward Tann, Junr., and See also: The effect of wedges was to See also:bend out the See also:side of the safe sufficiently to allow of the insertion of a crowbar between the body and the edge of the door, and various devices were adopted by different makers with the See also:object of resisting this mode of attack. These devices may be placed in three classes: (1) the fixing to the door of studs or projections which, when the door closed, passed into holes or recesses in the See also:frame of the body; (2) the use of bolts hooking into the side framing or entering the See also:bolt holes at an See also:angle; (3) the strengthening of the side framing and of the attachment of the bolts to the outer door-plate. The third of these methods (fig. 2) was patented by Samuel Chatwood in 1862, and is still very commonly employed. The second method was used by, Chubb and Chat-wood, but is not to-See also:day in general use. The first method was used by all makers of repute, but has now been abandoned, as the increased structural strength of the better class of safes renders such devices unnecessary. To prevent safes from being opened by the drilling of one or two small holes in such positions as to destroy the security of the lock itself, See also:advantage was taken of the improvements in the 4 774, r r // /7/j :..\ I_ /#/// Al r manufacture of high See also:carbon steel, and even in what is to-day called the " fire-proof " safe a plate of steel which offers considerable resistance to drilling is placed between the outer door plate and the lock. For many years little advance was made except such as consisted in substituting steel for iron and in general gaining increased strength by the utilization of better materials, although many safes are made and sold to-day which offer little if any more resistance to fire and thieves than those of 186o-187o. About 1888 the " solid " safe was introduced. In this the See also:top, bottom and two sides of the safe, together with the flanges at the back only or at both back and front, are See also:bent from a single steel plate (fig. 3). This construction, with solid corners, also illustrated in See also:figs. r and 2, only became practicable in consequence of the great improvements which had been made in the quality of steel plates; the See also:credit of its invention formed the subject of litigation, which, however, was not carried to an issue. The abolition of corner See also:joints, which up to 1888 had been made by dovetailing and by the use of angle irons, Had been previously attempted by See also:welding, but the See also:process was abendoned as commercially impracticable. In the early days of the safe industry in See also:America the conditions as far as See also:protection from fire was concerned were entirely' different from those obtaining in Great Britain. The See also:timber construction employed in See also:American buildings rendered fires much more fierce, but at the same time of very See also:short duration, not more than an Ng, ~/ sn~~no~a~~'s~n~nnn~~~navn~nna~~»o~.az:.%i\` •. I ~'Oiii\\\\\\,\/f~~\o~~~~\\~\\\\\\~~~~\~~~\\\\\\\\\\\\\\~~\\\\\\\\\\\\\\\\\\~~:~~V' %iii\\\~\\\~ './ FTn- I See also:hour or two, To meet this See also:condition of affairs thick sides of non-conducting materials were more efficacious than the chambers of steam-generating materials employed in See also:British construction, but the See also:gradual See also:abandonment of timber and the increasing size. of buildings have called for changes in the methods of fire-proofing. The American " burglar proof " safe (fig. 4) seems to have developed from the fire-proof (fig. 5) simply by the addition of extra thicknesses of metal, usually: alternately hard and soft, without any serious increase of structural strength; this construction, known as the " laminated " or " built up," offers little resistance to burglars, as the various layers can be separated from one another by the use either of See also:explosives, especially nitro-glycerine, or of -wedges. In 1890 a See also:commission was appointed, by the U.S.A. See also:government to See also:report upon the strong-rooms or ;vaults of the See also:treasury at See also:Washington; and their reports was presented in See also:September 1893. This commission' based their conclusions on experiments conducted in their presence, as well as on well-authenticated experiments performed by safe-makers on their own and other makers'. productions, and they found proof Safe. that, with the single exception of the Corliss safe, all the safe§' which came under their See also:notice—and these comprised all the best-known American makes—could be opened by burglars by s Report of Special Commission of Experts as to Means of improving' Vault Facilities of the Treasury See also:Department (Washington; 1894). In fire- and thief-proof safes, the body and door must be constructed of sufficient thickness, and the joints as well as the attachment of the door to the body frame of sufficient strength, to remain 'uninjured by a / fall from the highest position in which the safe may be placed to the See also:basement, or by the impact of any debris, See also:coping stones, girders, &c., falling from the highest part of the See also:building to the basement. The space between the outer body and the inner casing must be properly charged with a steam-generating mixture in sufficient quantity to keep the interior of the safe moist for the whole time during which it may be subjected to heat in the case of a fire. The same requirements must be satisfied in burglar-proof safes. In addition, the body and door must be of such material and of such thickness that it is impossible to cut a sufficiently large hole to See also:extract the contents, and so constructed that they can-not be dismembered; the framing and attachment of the bolts to the door must be able to resist the action of wedges or forcing screws; the vital parts of the lock and bolt-See also:work must be further protected so that it is impossible to attack them by drilling, and this protection must not be liable to be destroyed by the action of heat; the lock itself must not be capable of having its security destroyed by the See also:explosion of the largest quantity of explosive which can be inserted. If these conditions are satisfied there is little fear that the oxy-See also:acetylene See also:blowpipe, the electric arc or the use of the higher ex-See also:plosives can be made effective. The amount of protection required to meet the above conditions must, in each case, depend on what tools it is reasonable to anticipate may be employed by the burglar and the maximum time which he may have at his disposal. The use of high explosives has become a more frequent method of attack by burglars in Great Britain, but where the safes have been of the best quality, of solid construction and See also:good workmanship, this means of attack has been rendered ineffective. Strong-rooms and Vaults.—It is not hard to imagine that the use of strong-rooms was much earlier than that of safes; in fact, there can be no doubt that See also:masonry rooms provided with heavy wooden doors secured by locks were in use in ancient Egypt, and that the development of strong-See also:room doors attached to masonry rooms followed that of the old coffers very closely. No exact date can be obtained as to the introduction of what we may See also:call modern strong-rooms, but it is only reasonable to suppose that, where larger quantities of valuables had to be preserved than a safe would conveniently hold, a safe-door of larger dimensionswould be made and attached to a masonry or See also:brick room. The next step would be the See also:discovery that the walls of such a room offered little protection against even unskilled violence, and the lining of the room with metal would immediately follow; the door frame, as a matter of course, being attached to the plating. Strong-rooms of this construction are in See also:common use to-day by See also:banks and other institutions; and, as with safes, so with strong-rooms, development has taken place in the direction of increasing the thickness and the structural strength as well as in the application of See also:superior locking devices (see Locxs). This increase of structural strength has been carried along somewhat different lines by different makers in Great Britain and along still more diverse lines in America. Masonry or brick-work alone is now rarely relied on for the protection of goods of any great value; See also:concrete, however, reinforced by old railway metals imbedded therein and sometimes connected together to form, as it were, a cage, is in use. Railway metals attached to steel plates and also bedded in concrete are very largely employed. Thick plates of steel and latterly of manganese and other special steels are also in common use. Various forms of strong-room walls are illustrated in fig: 6. Usually a strong-room is provided with an open-work See also:gate or drilling, by the use of explosives, and by the use of wedges and s"milar well-known tools. This Corliss safe consists of a spherical See also:shell of cast iron several inches thick and with its exterior hardened by "chilling." It is fitted with a ground-in door rotating concentrically with the shell and internally. The spherical form and great thickness render the useful space in the interior very small and of inconvenient shape. The requirements of a modern safe may be briefly summarized. '=3 ll~llll~See also:lll~/,' / / / / / / H / H y' / / / / / / / b / / / / , / /, f Y'..e / / H H H H . L Y / H / / • , / / / H / / M H / / / / r % / / / / H /'/ / / / H / / N %. H r Y / / . / / / / H / / / H / / /e / / / / / / % / / / • • / / / / / / / / / H / / H / / / / / / b % / / / / / / / / / ~`'\ ~~~•~ :~%~• ~`ii`` ° ~ d% _\ \\ ~ t Vii/!i~~' e//z/4, FIG. 6. .0w o *44'. VVN .vvvvuvvA\eu~ wv.A~A\VVVV~ wvvvvv~O\vvvvvv~ sovvvvu~yVAVAVVOAV~~'~c:: v.,yacA\~~ :::u~'; ee-i "See also:grille" as well as a door, so that the contents may be protected The safety of the See also:Davy See also:lamp is endangered by exposure to a by the gate during business See also:hours without preventing the free access of See also:air; they are usually also fitted for convenient sub-See also:division. Safe See also:deposit vaults do not differ in any way from strong-rooms, except that they are fitted up with small safes or integers provided with special locks, so that the renter can gain access to his own integer only, and this only with the assistance of a custodian. Many See also:electrical devices have been introduced, having for their object the giving of an alarm when strong-rooms or safes are improperly approached or tampered with. Most of these devices were quite useless, as they could at once be rendered inoperative; but though others displayed greater ingenuity, it is very questionable whether they are of any real utility, and they have not remained in common use. Where the value known to be contained in a strong-room is sufficiently great, an attack by tunnelling must be specially guarded against, and as in this form of attack the time which may be devoted to preparing for the actual breaking through is practically unlimited, the use of some device which will give warning of any such attack before the See also:floor of the strong-room itself is reached is of very great importance. Probably the best of such devices, and one which is in practical use, consists of a network of small pipes, laid in concrete below the floor, and filled with See also:glycerin or other liquid. To this network a See also:mercury See also:manometer is connected. If any See also:breach is made in the See also:pipe system, a leakage takes place, causing an alteration in the level of the mercury in the manometer, which may, if desired, be arranged to See also:ring a See also:bell. The manometer should in any case be observed regularly on the opening of the strong-room. (A. B. CH.) SAFETY-LAMP, a form of lamp, used especially in mines, which is so constructed that it will See also:burn without igniting a gaseous explosive mixture by which it is surrounded. To effect this end, the See also:flame is encircled with a protecting metal case which is perforated with numerous small holes. Through these air for feeding the flame can enter freely and the products of See also:combustion See also:escape; but the flame or gases cannot pass out at a sufficiently high temperature to cause the ignition of the explosive mixture outside, because on arriving at the perforations they give up much of their heat to the large metallic surface they encounter, by which it is conducted away. In 1816 See also:Sir See also:Humphry Davy discovered the suitability of See also:wire See also:gauze as the material of the metal case, when the substance of the wire was rightly See also:pro-portioned to the size of the See also:aperture. The standard adopted as the limit for safety at that time was a gauze of 28 iron wires to the linear See also:inch, having 784 apertures per square inch, but in some lamps the apertures are occasionally made still smaller. The common safety or Davy lamp consists of a small cylindrical oil lamp, covered with a See also:cylinder of wire gauze about 6 in. See also:long and 11 in. in See also:diameter, with a See also:flat gauze top. The upper part of the gauze is doubled to prevent it from being worn into holes by the products of combustion, and the air for feeding the flame enters See also:round the See also:wick. The gauze is mounted in a cage, consisting of three upright wires, screwed into a flat See also:brass ring at each end. A handle is attached to the upper ring, while the See also:lower one screws on to a See also:collar on the oil-See also:vessel of the lamp. When the two parts are screwed together the lamp is locked by a bolt passing through both parts, which is screwed down flush with or below the surface of the outer ring, so that the gauze cannot be removed without the use of a key. In See also:Stephenson 's safety-lamp, generally known as the " Geordie " from its Inventor See also:George Stephenson, the See also:light is covered by a See also:glass See also:chimney, surrounded by an outer casing and top of wire gauze. The feed air is admitted through numerous small holes in a See also:copper ring a little below the level of the wick. This is one of the safest forms of lamp, but requires considerable care in use, especially in keeping the small feed holes clear from dust and oil; the glass protects the gauze from becoming overheated, and when the air is dangerously charged with See also:gas the light is extinguished. In the lamp invented by Dr W. See also:Reid Clanny (1796-1850) about the same time as those of Davy and Stephenson, a glass cylinder is substituted for the lower portion of the wire gauze. The air for supplying the flame, entering at the bottom of the gauze and passing down the inner side of the glass, protects the latter to some extent from becoming overheated, but a large amount of light is lost by absorption in the glass, so that there is no great advantage over the See also:ordinary Davy lamp to compensate for the extra See also:weight and cost, especially as the safety See also:property of the lamp depends upon the glass cylinder, which may be readily broken when subjected to the ordinary accidents of working. A more perfect form of lamp of the same See also:character is that of Mueseler, which is extensively used in See also:Belgium. It differs from Clanny's lamp by the addition of a conical chimney above the flame, which produces a rapid See also:draught, and consequently a more perfect cooling of the glass cylinder by the downflow of feed air for the flame.
current of gas moving at more than 6 ft. a second, as the flame is then liable to be forced through the gauze, and the Clanny and Stephenson lamps are not safe in currents exceeding 8 and it) ft. respectively. These early forms have therefore been improved and modified to meet the requirements of safety in air-currents travelling at a high velocity. In the See also:Hepplewhite-See also: Special care is, however, required in filling, so that no free liquid may be See also:left in the holder; the spirit must be entirely absorbed by a filling of sponge, and any superfluous quantity poured off. Portable electric lamps, supplied by accumulators or dry batteries, have been introduced into See also:coal- mines; but owing to the weight and cost their use is as yet very restricted. The ordinary safety-lamp affords indications of the presence of fire-damp (See also:marsh gas) in the air of a mine. When the amount exceeds 2 or 2y %, it may be detected by reducing the flame till it is practically non-luminous, when a See also:pale See also:blue flame or luminous cap will be seen above the ordinary flame. This varies in size with the percentage of fire-damp, until when there is about xo% the blue flame fills the whole interior of the gauze cylinder. If the lamp is allowed to remain too long in such a fiery See also:atmosphere, it becomes dangerous, because the gauze, becoming heated to redness, may fire the See also:external gas. For detecting the presence of fire-damp in amounts less than 21%, special lamps with non-luminous flames are adopted. In Pieler's lamp, which is of the ordinary Davy form, See also:alcohol is burned on a See also:silk wick, and a See also:screen is provided so that the flame can be hidden. When exposed in air containing I% a cap of 1i in. is formed, which increases to 2 in. with 1 %, and with 1 I% the lamp is filled with a deep blue glow. Another and more useful method is that of Dr F. Clowes, who uses a See also:hydrogen flame 0.4 in. long, obtained by attaching a cylinder containing compressed hydrogen to an ordinary safety-lamp. When used for gas testing the hydrogen is turned into the oil flame, which is for the time extinguished, and relighted when the observation is finished. So small a proportion as 0.2 % of gas can be detected by this method. The locking of safety-lamps, so as to render them incapable of being opened by the miners when at work, is a point that has given See also:play to a large amount of ingenuity. One of the most favourite devices is a combination of the wick-holder with the locking bolt, so that the latter cannot be withdrawn without lowering the wick and extinguishing the flame. Another method consists in the use of a See also:lead See also:rivet, uniting the two parts of the lamp, impressed with a See also:seal, which cannot be removed without defacing the device. All this class of contrivances have the defect of only being efficacious when the miners are not provided with matches or other means of obtaining a light. A more physically perfect method is that adopted by See also:Bidder, where the locking bolt is magnetized and held in place by a force which can only be overcome by the application of a See also:battery of heavy and powerful steel magnets. These are kept in the lamp See also:cabin at the See also:pit bottom, where the lamps are cleaned and served out lighted to the miners at the commencement of the shift, and are collected before they return to the surface. (H. B.) $AFFARIDS, a See also:Persian See also:dynasty of the 5th century, founded by Yakub (Yaqub) b. Laith h. Saffar (" coppersmith ") about 866, who, originally a See also:leader of bandits and outlaws, became See also:governor of Sejistan. He soon added to his See also:province See also:Herat, See also:Fars, See also:Balkh and Tokharistan, overthrew the Tahirids in See also:Khorasan, and, nominally still dependent on the caliphs of See also:Bagdad, established a dynasty in Sejistan (see See also:CALIPHATE, See also:section C, See also:Abbasids, § 10, and See also:PERSIA: History, section B). Soon after 900 the dynasty became subordinate to the See also:Samanids (q.v.) and few of its rulers had any real authority. Under the last of the dynasty, Taj ud-din Binaltagin (1225-1229), a usurper of the royal See also:family of the Khwarizm shahs, the See also:country was captured by the See also:Mongols. See S. See also:Lane See also:Poole, See also:Mahommedan Dynasties (1894), p. 129 ; Stockvis, See also:Manuel d'histoire (See also:Leiden, 1888), vol. i. p. 137; on the later $affarids, H. Sauvaire, in the Numismatic See also:Chronicle (1881). Additional information and CommentsThere are no comments yet for this article.
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