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reduce the height of the side walls of the building, but would appear to make a very much cheaper construction, and is worthy of being closely looked into. The arrangement shown on the large drawing [see plate] is the one about to be erected at Edinburgh at the new works.

The coal is received in railway waggons on sidings running at the general yard level. A pit is formed beneath a double line of rails on the transverse centre line of the retort-house, in which is placed the coal breaking and elevating appliances. The waggon is discharged by means of a hydraulic lift placed between the rails. This, ascending, catches the hind axle, lifting one end of the waggon as a consequence, and emptying its contents upon

FIG. II.-PROPOSED CONSTRUCTION OF ROOFS SUPPORTED UPON STRUCTURAL IRONWORK FOR INCLINED RETORT Bench.

a traversing plate or picking belt. The speed at which this is made to travel depends upon the class of coal received at the moment, thus regulating the feed to the coal-breaker, where the coal is broken to a uniform size, falling immediately from the breaker into the boot of the elevator. The elevator transports the coal from the base of the pit to the highest point in the retort-house, at which point it discharges on to a pair of conveyors, each of which feeds one of two lines of conveyors at will, running longitudinally with the building. Immediately beneath these longitudinal conveyors, there is a continuous trough or hopper formed, sufficient in capacity to carry about 14 hours' stock of coal. Immediately below the storage hopper, measuring chambers are fixed to gauge the weight of the charge for

each individual retort. This chamber is actuated on the old powder-flask principle, by means of a sliding door at the top and at the bottom actuated by one lever, so that when the upper door is open the bottom one is shut. In order to prevent the bye-passing of the coal when the levers are at half stroke, a` counterbalance flap is introduced at the bottom of the measuring chamber, which cannot fall and open the bottom port until the bottom slide is fully drawn, and consequently the top slide fully closed. With this arrangement, it is possible to regulate the weight of the charge over a lengthened period of time without its varying more than a few pounds every time the chamber is discharged. The coal is conducted to the upper mouthpieces by means of a traversing shoot (one shoot being provided for each tier of mouthpieces), within which provision is made for baffling the fall of the coal so as to permit of a steady flow into the retort. The settings at present constructed at New Street are working four charges of 7 cwt. each charge, and, as before explained, are constructed with fire-clay blocks and Glenboig retorts.

I find that when carbonizing shale and cannels alone we have some difficulty in maintaining the full heat necessary for any lengthened period of time. This is perhaps accounted for by the depreciation in the quality of coke going to the producers, and also by the greater heat required in obtaining the gas from the cannels and shales. When mixed, however, in the proportions of 33 per cent. of cannel to 67 per cent. of splint coal, there is no difficulty whatever in maintaining a sufficient heat throughout the setting.

The coke in being drawn from the retorts comes in contact with a traversing screen at the back of which the men work; one screen covering a whole setting of retorts, with three vertical slots in it sufficient to enable the pricking-rods to pass through. The men by this means are completely protected from the heat necessarily arising from the fronts of the settings, and the discharging coke. The screen directs the coke, through openings in the stage floor, into waggons suspended on an overhead single line. By means of the water-quenching arrangements shown, the men on the stage floor can open the valve and allow the coke to be quenched in the waggons without going to the ground floor; the steam arising passing up the fronts of the settings clear of the operators. These waggons are drawn from the retort-house by means of a continuous wire rope; and it is intended that they should pass up an inclined plane to the over. head arrangements which are to be put down for the stacking

of the coke in the yard, or the discharge of the same over screens into railway waggons.

The greater part of the condensing appliances are contained within the retort-house; the lines of pipes being nestled within the triangular space above the haunches of the main girders of the roof. It should be noted that the gas-main passing from the foul main at the back of the hydraulic-mains has a gentle rise, and continues to rise throughout the seven lengths of 20-inch piping running the full length of the retort-bench. This same system is carried out at Huddersfield, and was found to yield considerable advantage from an absorption of some of the lighter hydrocarbons by the gas-the lighter oils depositing from the gas as they cool flowing in the reverse direction to the stream of gas, the hot gases taking up some of the lighter vapours-not only producing a somewhat higher illuminating power, but tending greatly to bring about uniformity in the quality produced from hour to hour. From this point, the gas passes through the exhausters, and finally through water-tube condensers and through the other general routine, which the present paper will not permit of my dealing with.

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FIG. 12.-DIAGRAM SHOWING PROPOSED SETTING OF TWELVE

22 IN. BY 12 IN. Retorts, TO BE CONSTRUCTED WITHIN AN EXISTING SETTING OF NINE 22 IN. BY 15 IN. RETORTS.

I may mention, however, that it is my intention to construct within the inclined retort bench at present working at New Street -when the same requires re-setting-a setting of retorts similar to that shown on the preceding diagram (fig. 12). The size of the archway is, of course, the same as is at present occupied by nine retorts; but it is my intention to try the form of retort shown, and put in a setting of twelves. Whether this will be a success or not, it would be premature to predict. From a practical point of view, however, there does not appear to be any reason why it should not be a success so far as construction and wear and tear are concerned. My only fear is that the heating of a setting working such heavy charges at the rate of six charges per retort per day—in all 25 tons per setting-may be somewhat difficult to maintain.

Discussion.

The PRESIDENT said they would all agree with him that Mr. Herring had given them an intellectual treat. He had gone over a field that was new to them. For many years he himself had been making inquiries regarding installations of inclined retortsettings; but there was always something wanting in the information he obtained. They had now before them a complete treatise on the construction and working of inclined retorts. Mr. Herring was the first to introduce inclined retorts in Scotland, by way of experiment; and he was so confident of the results, that he was now putting up one of the largest installations in the world. He was sure, from the drawings that were before them, that it would be one of the finest. Mr. Herring, he had no doubt, would be very pleased to answer any question in regard to the different points he had dealt with.

Mr. H. POOLEY (Dunfermline) said in the month of March he reported to his Commissioners on the subject of sloping retorts, along with others; and his opinion in regard to such retorts was that the capital cost of them was very high. He should like to ask Mr. Herring to give them some approximation of the capital cost per mouthpiece, and also to ask him whether he was right in saying that it came to about £120 or £130. This figure was at least 60 per cent. more than the cost of regenerative settings. Then he found that for a works of the size of those at Dunfermline, where the difference in the manufacture in the summer time was so great-their minimum being 70,000 cubic feet, and their maximum over 500,000 cubic feet-there really was nothing in sloping retorts as against retorts set on the regenerative principle.

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