April 30, 1915. THE COLLIERY GUARDIAN. 911 The Rothwell No. 3, Miners’ Electric Safety Lamp. The Rothwell No. 3, Miners’ Electric Safety Lamp, the general design of which is shown in fig. 3, possesses the following essential features :— (1.) A case of steel, brass or aluminium, provided with a securely riveted or soldered brass screwed locking ring. (2.) An electrical accumulator, the terminals of which are fitted with spiral or other springs carrying rubbing brass contacts; the construction of the accumulator being such as to prevent escape of the liquid, whatever the position of lamp, whilst allowing the escape of gas generated by chemical action. (3.) A cover forming a flametight connection with the case and consisting of a middle base ring of brass or steel carrying an aluminium or steel crown supported HALF EL EVATI O N j HA.LF SECTI ON c Fig. 3.—Rothwell No. 3 Miners’ Electric Safety Lamp. by four or more brass or steel pillars. The middle base ring is screw-threaded internally to take a celluloid glass retaining plate. A stout protecting glass forms flametight connections with the crown and retaining plate by wrashers of asbestos or other suitable material. The glass retaining plate also carries the lamp-holder and an insulated electrical contact piece. (4.) An eflicient looking device securing the cover to the case, consisting of a lead-rivet lock with a hinged hasp or lug securely attached to a sliding band on the cover, and a staple or lug securely attached to the case. (1) The total weight of the lamp shall be not more than 5J lb., and the lamp must have been made at the works of Messrs. J. H. Rothwell and Company, at Sindsley, Swinton, near Manchester. The Worsnop Miners’ Electric Safety Lamp. Fig. 4.—Worsnop Miners’ Electric Safety Lamp. The Worsnop Miners’ Electric Safety Lamp, the general design of which is shown in fig. 4, possesses the following essential features:— (1.) A cylindrical case of steel. (2.) A stamped steel cover, which is secured to the case by a bayonet flame-tight joint and locked by a magnetic lock of the type shown in fig. 4, so constructed that the two bolts can be withdrawn only by placing the poles of an electro-magnet to the faces of the locks. (3.) A plate of steel fitting a recess in the top of the cover, carries the incandescent bulb, lower reflector, and protecting glass. The crown of the lamp, to which four pillars are riveted, consists of a ring of steel, the under- side of which is recessed to hold a circular lens or steel disc and metal reflector, and to form the upper seating of the protecting glass. The pillars attached to the crown pass through holes in the bulb carrier plate and slots cut in the cover, and are secured to a flanged metal ring by nuts on the underside. The flanged metal ring carries an insulated disc fitted with switch contacts, and makes a flametight joint with the cover. The protecting glass makes a flametight joint with the crown and bulb carrier plate by means of asbestos or other suitable washers. (4.) An electrical accumulator, fitted with two terminal lugs, and so constructed as to prevent escape of the liquid, whatever the position of the lamp, whilst allowing escape of gas generated by chemical action. The total weight of the lamp shall be not more than 5 lb., and the lamp must have been made at the works of Messrs. Worsnop and Company, at Halifax. Amendments to the Previous Schedules. Flame Safety Lamps. In the description of the Cremer Lamps, No. 11,* * * § No. 11a,f and Cremer Marsaut Lamp. No. 15J, shall each be amended to read as follows :—“ That the lamp has been made at the works of the Cremer Lamp and Engineering Company Limited, formerly at 32, York- place, Leeds, or at the Company’s Moorfield Works, Whingate, Wortley, Leeds. 2. The Davis Magnet Lock for Safety Lamps, a diagram of which is given in fig. 5, is approved as a lock to be fitted to approved safety lamps, provided that the material of which it is made is of strength not less than that of the sample submitted for official test on January 13, 1915. Fig. 5.—Davis Magnet Lock. The lock is a padlock, the bolt of which can be with- drawn only by a powerful electro-magnet. The bolt can pass through such lugs or staples as are commonly fastened on the bottom ring and oil vessel of a lamp to receive a lead rivet. 3. In the description§ of the No. 1 lamp, it is now provided that there shall be provided a lead-rivet lock, with a hinge or lug securely fastened either to the bottom ring or to a pillar, or to a sliding band on the bottom ring, and a staple or lug securely soldered to the oil vessel, or a lug with two or more holes cast on or securely soldered to the oil vessel. 4. In the description]] of the “ Bifold Burner Marsaut ” and the Marsaut “A” lamps, the bonnet or shield may be of seamless steel, and there may be four pillars. 5. In the description]] of the Bifold Burner Marsaut, the Marsaut “ A ” and the Marsaut “ C ” lamps, it is provided that in lamps which were introduced in mines MIDDLE PART A &A. MIDDLE PART 8 MIDDLE PART B & B2 Fig. 6.—Alternative Arrangements in Gauzes in Naylor’s Marsaut Lamps. before July 1, 1914, the arrangement of the gauzes in the lamp may be one of those shown in fig. 6 of this Order, the flange of the middle collar being cut away in sections, or altogether, to expose the gauze rings, thus * See Coll ery Guardian, September 12, 1913, p. 524. f See Colliery Guardian, October 24, 1913, p. 854. X See Colliery Guardian, May 1, 1914, p. 968. § See Colliery Guardian, September 19, 1913, p. 581. |] See Colliery Guardian, September 26, 1913, p. 643. making it possible readily to ascertain the absence or presence of the gauze on an external examination. A lead-rivet lock may be used with a lug on the bottom ring and a flange on the oil vessel perforated with a series of holes in order that wear in the screw- threads of the oil vessel may be taken up. 6. In the description* of the Marsaut“ E ” lamp the title of the lamp shall be the “ Marsaut E or Marsaut E 1 lamp,” 7. In connection with the description^ of Patterson and Company’s lamps, Types B 3 and B 4, an alternative types B3. & B4 TYPES B5. &B6. TYPE. D|. Fig. 7.—Arrangement of Gauze in Messrs. Patterson and Co.’s Lamps. arrangement, which prevents the lamp from being put together without its gauzes, is shown in fig. 7 of this Order. 8. In the description^ of Patterson and Company’s lamp, Type D 1, the same additional observation is made. 9. Teale’s “ Protector Lamps, Nos. 1, 2 and 1a, and Standard Bonneted Marsaut Lamps Nos. 4 and 4a.§— These lamps may be fitted with removable bonnets or shields of a screw-off type, provided or not with shut-off rings with vertical inlet holes of total area not exceeding IT sq. in. The bonnet is locked to the middle or pillar ring by a sliding pillar kept in position by the oil vessel. 10. In the description]] of the Cambrian lamps No. 1 and No. 3, each lamp may be fitted with a Mueseler chimney and horizontal gauze, as shown in fig. 8, in place of the inner gauze, the horizontal gauze forming a flame-tight connection with the Mueseler chimney, and FITTED WITH MUESELER CHIMNEY CAMB i LAMP Fig. 8.—Modifications in the Cambrian Lamps. (E. Thomas and Williams.) the brass ring to which the gauze is attached forming a flame-tight joint with the brass ring of the outer gauze. The dimensions of the Mueseler chimney are as follow:— In. Length of chimney above horizontal gauze, not less than...................................... 3f Length of chimney below horizontal gauze, not less than ..................................... t76 Diameter at top, not greater than ............... A Diameter at bottom, not greater than ..»....... If The Cambrian No. 1 lamp, in addition to the Mueseler chimney, may be fitted with a glass extension supported on a frame of brass or aluminium attached to the oil vessel, as shown in fig. 8. In this case the dimensions of the Mueseler chimney are as follow:— In. Length of chimney above horizontal gauze, not less than ....................................... 21 (wit h a cap 1 in. in diameter fixed f in. from the top) Length of chimney below horizontal gauze, not less than ........................................ i Diameter at top, not greater than ............. If Diameter at bottom, not greater than .......... 1 * See Colliery Guardian, October 31, 1913, p. 905. t See Colliery Guardian, May 8, 1914, p. 1010. t See Colliery Guardian, May 15, 1914, p. 1069. § See Colliery Guardian, October , 17, 1913, p. 802; October 31, 1913, p. 905; May 15, 1914, p. 1069; and November 13, 1914, p. 1021. || See Colliery Guardian, October 24, 1913, p. 853.