18 iff.] Liferaiy (Old Philosophical Intelligence. ^40 



ed me a lamp which, tIioii<;li it had been A brass pipe was now fixed upon the 



in use about sixteen hoiii's aday for nearly blower tube, so as to make the whol« 



three months, was still in excellent condi- stieani pass throuj^h an aperture of less 



tion; he also said it had been red hot than half an inch in dianietor, which of 



soiuetimes for several hours toycthei-. conise formed a most powerful blow-pipe, 



Wlierever workmen, however, are exposed from which the fire damp, when inHame d, 



to such highly explosive mixtines, double issued with i^ieat violence, and a roaring* 



gauze lamps shoidd be used, or a lamp in noise, making an intense flame of the 



which the circulation of the air is dinii- len^tli of five feet. The blow pipe was 



Dished by a tin-plate reflector placed iu exposed at right angles to a strong wind, 



the inside, or a cylinder of glass reaching and the double gauze lamps and singl* 



as high as the double wire, with an aper- lamps successh'ely placed in it. The doti- 



ture in the inside; or slips of Muscovy b!e gauze lamps soon became red-hot at 



glass may be placed within the Ian p, and the point of action of the two currents, 



iu this way the quantity of (ire-damp con- but tlie wire did not burn, nor did it com* 



sunied, and consequently of heat pro- municate explosion. 'J"he single gauze 



«luced, may be diminished to any extent, lamp did not communicate explosion, as 



Such lamps likewise may be more easily long as it was red hot, and slowly nioved 



cleaned than the simple wire-gauze lamp ; thiou^h the currents; but, when it was 



for the smoke may be wiped otf in an iu- fixed at the point of most intense conibus- 



staut from the tin-plate or gla'is.* tion, it reached a welding heat, the iron 



If a blower or strong current of fire- wire began to burn with sparks, and the 



damp is to be approached, double gauze- explosion then passed. 

 lamps, or lamps in which the circulalion In a second and iliird set of experiment* 



•f an- is interrupted by slips of metal or on this violent blow-pipe of fire-damp, 



$:lass, should he used ; or if the single lamp single lamps, wi*h slips of tin-plate on the 



be employed, it should be put into a com- outside, or in the inside, to prevent Ihe 



mon horn or glass lanlhoin, the door of free passage of the cm rent, and double 



which may he removed or open. lamps, were exposed tj all the circnm- 



The wire-gauze is impeimeable to the stances of the blast, both in the open air 



flame of all currents of fiie damp, as long and in an engine-house, where the atmos- 



as it is not heated above redness j but, if pliere was explosive to a groat extent 



the iron wire be made to burn, as at a round the pipe, and through which there 



strong welding heat, of course it can be was a strong current of atmospheric air; 



no longer safe ; and though such a circum- but the hear of the wire never approached 



stance can, perhaps, never happen in a col- near the point at which iron-wire burns, 



)iei-y, yet it ought to be known and guard- and the explosion could never be conimn- 



ed against. Ajid if a workman, having a nicated. The flame of the firedamp 



single lamp, should accidentally meet flickered and roared in the lamps, but did 



a blower acting on a current of fresh air, uoi escape from its prison. 

 he oucht, on finding his lamp becoming There is no reason ever to expect a 



hot, to take it out of the point of niixtui e, blow-pipe of this kind in a mine ; but, if it 



•r screen it from the current. should occur, the mode of facing it and 



I have had an excellent opportunity of examining it, witii mcst perfect security, 

 making experiments on a most violent is shewn; and the lamp others a resource, 

 blower, at a mine belonging to J. G. which can never exist in a steel-mill, the 

 Lambt.n, esq. some of thini in the pre- sparks of which would undoubtedly in. 

 icnce of Mr. I/amblcn ; in most of them flame a current of this kind. 

 Wr. IJuddle assisted. This blower is wall- Arguments have been stated as to the 

 f (I ofl' from the mine, and carried to the weakness of the lamps. In a board or 

 •iirface, where it is discharged with great gallerv in the Wallsen J colliery, Mr. Bud- 

 force. It is made to pass through a die and myself, with some of ihe viewers, 

 Jcathern pipe, so as to give a stream, of endeavouied to inji;re a single gauze lamp 

 «hich the force was felt at about two feet by throwing large pieces of coals upon it, 

 from the aperture in a ."trong current of and striking it with a pick ; but we never 

 air. The conmion single workint; lamps perfotated the gauze, and the lani)), after 

 •lid double gauze lamps were brought upon these severe trials, burnt with perfect sc 

 this current, both in the free alwosphere curity in a small explosive afmosphci-p, 

 and in a confiin-d air. The gas fired in made by Mr. IJuddle at the bottom of th« 

 tlie lamps in various trials, but did not shaft for the purpose of tryiuL' the lamps. 

 Ileal them abo\e dull redm-.'^s, and when 1 made, with Mr. ijnddle and his 

 they weie brought lar into the strcani they viewers, some (Xperimenls on the cornpn- 

 were finally extingiii vhed. rative light of Ihe lamps, the common mi- 



• Models of ihe diii'i rent modKJcatioiu iiersTandlc, and the sti.»l mills, in a ga!- 



•f the wire-gauze safety-lamps may be seen lery in the Wallsend colliery. We judged 



at the shop of "Mr. Coxe, brass-fcunder, in of "the inieiisily of the light by the square 



Ciate-'hrad, by whom ilicy were made. •' lkedi»t4ucc at which a small object was 



AIoM HLV ^vci. No! -JbUv ^ ^ >i.sibl«; 



