28,409. Fairweather, W., [Marquette Electric Co.]. Dec. 27. Arc lamps; supporting lamps.-Clutch lamps with enclosed arcs are constructed and supported as shown in the Figures, whereof Fig. 1 represents the whole lamp, Fig. 2 the upper part of the lamp seen at right-angles to Fig. 1, Fig. 7 the switch in bottom plan view. Fig. 9 the upper carbon-holder, Fig. 11 the regulating -solenoid and dash-pot, and Fig. 17 one device for supporting the lamp. The frame consists of two bars 2 attached to atop casting 4 and to a porcelain cup 3, and consisting of steel rods encased in brass tubes. Washers upon the-rods extend beyond the bottom edge of the cup 3 and support a thin-walled, metallic, heat-dissipating chamber D, having a flange 11 which is forced over a reduced shouldered part of the cup. In the bottom of the chamber D is a large hole surrounded by a thin flexible edge 11<d>, against which the upper edge of the globe G rests so as to form a tight joint, and within the chamber D is a division device consisting of a short tube 12 having a wide flange 12<a> and supported by lugs or rivets 12<b>. The globe is preferably supported by a spring wire bail, the upper ends of which are hooked into lugs 13 on the bottom of the heat radiator D. In a central hole in the cup 3 is secured a gas check 6, consisting of a metal or lava sleeve with internal grooves 6<b>. A rod 7, supporting the negative carbon-holder 7, passes through the cup 3 and is secured in place by a nut on each side. The casing consists of a metal hood 10, secured to the plate 4, and of cylindrical parts 10<a>, 10<b> united by large-bodied rivets 10<d>. Lugs 10<c> on the part 10<a> serve to centre it within the hood 10, and the parts 10<a>, 10<b> are supported by struck-down lugs 5<a> on an annular metal disc 5, which engage a notched flange 10<e> on the part 10<b>, and hold the flange against the underside of the disc 5. By turning the casing round till the notches in the flange 10<e> register with the lugs 5<a>, the casing is freed and can be lowered to uncover the working parts of the lamp. Chains 10<f> support the casing in its lowered position. The upper carbon-holder consists of a cap 8, Figs. 2 and 9, having in its side a hole 8<a> opening into a larger threaded recess 8<b>. Into this recess screws a cup 8<e>, containing a spring which presses a flanged head 8<c> against the carbon P, and provided with a screw 8<g> for securing the terminal 14<a> of a cable 14. Secured by screws to the top of the cup 8 is a block 15, Fig. 2, of porcelain or other non-corrosive material, grooved at the ends so as to fit the rods 2 loosely ; in another form, shown in Fig. 9, the block 15 is replaced by a clip 15<d>, insulated from the holder and containing rollers 15<c> which engage the guide-rods 2. The end of the upper carbon is forced into the holder 8 and presses back the spring head 8<c>. A lug 4<b> on the top-plate 4 limits the upward movement of the holder. The clutch lever C has in its underside a recess 16<c>, which, when the clutch is lowered, is engaged by the upper end of the gas check 6. The lever C is connected to the core of the solenoid S by means of a link 16<d> and an insulating-coupling, Fig. 11, comprising a metal part 18<b>, a lava insulator 18<c>, and a metal union 18<d> screwed on to a brass tube 18<a> encasing the core. The solenoid is of the iron-clad type, and has an inner iron tube 17, brass and iron ends 17<a>, 17<b>, and an iron sheath 17<d>, which extends above the solenoid and is closed by a screwed, inverted, metal cup 19, having lugs 17<e>. A link 17<f> is pivoted to the lugs 17<e> and attached to a boss 4<c> in the plate 4. The lower part 19<a> of the cup 19 forms the cylinder of the dash-pot, the piston of which is a metal disc or cup 20 attached to the tube 18<a>. A bye-pass 19<d>, connecting the two parts of the cylinder 19<a>, is provided with a regulating-screw 19<f> and locking-nut 19<g>. If desired, the dash-pot may be constructed so as to allow of a more rapid downward than upward movement of the core. In this case, the tube 18<a> is closed by a screw plug 20" with a flange 20b, between which and a washer 20<e> the piston 20 has a little play. The washer 20<e> is secured between a nut and a shoulder on the plug 20<a>, and is provided with projections 20<f> against which the piston rests when the core descends, so that air can pass from one side of the piston to the other. The resistance R, Fig. 1, consists of a wire wound in a spiral groove of an insulating-spool. This spool is made in two sections, provided with central square holes to receive a square bolt, the ends of which are turned and fitted with nuts 23<a>. The upper end of the bolt screws into a boss 4<d> on the plate 4. Each section of the spool has a head 22<a> with perforated lugs, in which are secured binding- posts for the ends of the wire. The upper binding- post (not shown) is short, while the lower one 21<a> extends upwards for some distance, and serves also as a stop for a metal band 24, which can be tigbtened over the spool by means of a screw 24<a> and serves for the adjustment of the resistance. The path of the current from one terminal of the lamp to the other is through switch contact-pieces 29, Fig. 7, a cable 26, band 24, resistance R, cable 14, carbons P, N, rod 7<a>, cable 35, solenoid S, and a cable 28. The switch arm 34 is held on its shaft 33 between a square washer 33<1>, having bent-up sides, and a nut 33<a>. On the top-plate 4 is a threaded boss 4<e> and a yoke 9 containing a porcelain hanger spool 9', and having a central opening larger than the boss. The yoke 9 can be adjusted on the plate so that the lamp may hang vertically. Where there is little overhead room for the lamp, a hanger-board, Fig. 17, is preferably employed. Attached to the conduit pipe 30 by a nut 30<a> or other means is a block 31 of porcelain or like material, carrying metal boxes 31<a>, slotted along the bottom and open at opposite ends. The boxes 31<a> are connected to the cables, and have recesses 31<b> to receive nuts 27 on the binding-posts of the lamp.