17,635. Levy, L. E. Aug. 31. Etching; bronzing and the like.-Relates to a machine for applying etching-resist powder to prepared plates, fusing the powder on the plates, and, finally, cooling the plates. Thepowderapplying apparatus comprises a table 1, Figs. I, II, and V, carrier chains 11, hoppers 53, 54 for alternative use and adjustable for varying the feed, devices such as feedscrews 55 and brushes 56 cooperating with the hoppers, flat packing-brushes 62 working in a chamber 66, and a fan 78 working in a casing 67 communicating with the chamber 66. The corresponding screw 55 and brush 56 are geared together, and the brush 56 is driven from a screw 61 through a deeptoothed gear 60 allowing of adjustment, around the screw 55, for thickness of plate. The brush 56 is adjusted, or rendered inoperative, by means of a rockshaft 57 provided with a handle; trip-levers on the shaft 57 are engaged by lugs on the chains 11 to raise the operative brush 56 when a plate has passed beyond it. Grid openings 2, 3 are formed in the table 1 for the escape of waste powder into receptacles below. The transverse bars of the grid for the first opening 2 serve to remove surplus powder from the brush 56 before the plate reaches it. The brushes 62 are attached to endless chains 63 carried and driven by sprocket-wheels on shafts 64, 65, mounted in vertically-adjustable bearings. Shields 68, 69 bend the brushes 62 ; undue bending of the hairs is prevented by rubber or like strips 70, which may be reinforced by metal strips 71. The sprocket-wheels on the shaft 64 are recessed to receive the cross-bars of the links of the chains 63, so that the brushes 62 have a rocking movement. The brushes 62 enter converging recesses 4 in the table 1, for separation of the hairs and removal of powder, and sweep out any powder through the opening 3. The fan 78 draws air into the chamber 66 through the openings below the shields 68, 69, and also through an opening 79 to impinge against the brushes 62 as they leave the shield 69. The furnace comprises longitudinal framework bars 5, Figs. I, II, and XII, carrier chains 13, gas burners 6, deflectors 84, 85, a hinged cover 83, and a flue 82. The gas-supply pipe 87 is connected with a transverse pipe 88, from which extend air mixers leading to the burners 6 through pipes having regulating-valves. The burners 6 are lighted by a pilot-light 90. In addition to an ordinary cut-off valve, the pipe 87 is fitted with a valve 91 controlled through gear 92, 50 ; a valve by-pass 89 permits use of the furnace independently. A plate 80 prevents entrance of heated air into the chamber 66. The cooling-apparatus comprises a ribbed table 9, Figs. II and XIV, carrier chains 14, a rotary blower 95, Fig. I, and chambers 7, 8 connected with the blower and arranged to discharge below and above the plate. The parts are driven as follows :-A belt-driven shaft 38, Figs. I, II, and V, is provided with a gear-wheel 39 driving a pulley 42 for the fan 78, a gear-wheel 40 driving the parts 56, 62, and a gear 37 driving a worm shaft 36 and connected shaft 28. From the shaft 28 are driven the chains 11 by a chain 43, the chains 13, 14 by a chain 26 and common shaft 22, and a shaft 46 by a chain 44. The shaft 46 carries the gear 50 for the gas-supply valve 91, a trip arm 51 co-operating with a belt-shifter 52 for the shaft 38, and a cam 47 engaged by a rock-arm 48 operating a beltshifter 49 for a shaft 100 driving the blower 95.