332 THE COLLIERY GUARDIAN. February 14, 1913. Types of Shaft Suspension. Cleats.—No definite rules can be laid down as to the permanent installation of vertical cables; but there can be no doubt that the most desirable arrangement is a cleat of the sitting type resting on the inner, or wall sides, either of existing buntons or on segmental H girders erected for the purpose. The cleat should be of some hard wood, creosoted. The actual class of timber will depend on the pit water, and may be best left to the judgment of those who know the pit. An average cleat should not be less than 2 ft. 6 in. to 3 ft. long, and should be provided with at least three sets of % in. bolts and iron straps g in. thick back and front. The bores that take the cable should be cut to the exact diameter of such cable. It should be realised that the grip depends on friction, and that direct pressure is only a component thereof. All wood cleats should be fitted with wrought iron roofs to throw off water and falling bodies. Other types of wooden cleat there are—for clipping round buntons, for bolting through buntons, for fixing to wire ropes, and for fixing to tubbing direct to the brickwork, &c. Of these, however, the two last are subject to a possible shearing strain, which is mechani- cally wrong. Single Suspension.—Many colliery engineers insist on having an absolutely clear shaft, and in shallow pits it is possible to instal with a single suspender, built on the capel or wedge principle, with the outermost armour of the cable taking the weight. This certainly has the advantage of offering no obstacle to break the fall of dropping material, but the use of such a fitting (except, perhaps, for short lengths of paper lead covered cable) is to be deprecated, as the strains set up in the cable are obvious, and have sometimes led to breakdown immediately under the suspender, where, of course, the strains are most concentrated. In the suspender illustrated (fig. 4) three-quarters of the breaking stress of the armour may be reckoned on, so that if the armour be designed with a breaking stress of eight to ten times the weight of the cable, the safety factor of the installed cahle is from 6 to 7’5. Continuous Vertical Casing.—This, since the issue of the new rules, need hardly be considered, as. the necessity for it—namely, the instalment of unarmoured or merely lead-covered cables in wet shafts—is not likely to arise. Methods of Lowering Shaft Cables. These again largely depend on the gear at hand and on shaft conditions. The more usual methods are : (1) lashing to a steel wire rope ; (2) direct from cage ; (3) raising from pit bottom ; (4) lowering by capstan or winding engine; (5) by means of locomotives. To Lower by Attaching to Haulage Ropes.—The safest way, from the cable point of view, is to fasten the cables by lashings or small specially made clamps, to a wire rope controlled by a hauling engine. The discriminate use of a plank brake on the cable drum flange will help to prevent the cable hanging in festoons about the wire rope as it descends. The best material for lashings is ordinary spun yarn of f or J inch diameter. It should be used double, and each tie should carry about 1 cwt. of the weight of the cable. The above method is, of course, unsuitable for single suspension or casing. A slight wave in the cable after laying is no dis- advantage. For the same reason, it is advisable that an interval of 12 hours or so should elapse after lowering before cieating is commenced. To Lower Direct from the Cage, with the drum slung either inside or underneath, can only be effected when there are no buntons in the shaft or when cleats are attached to their outer sides. Means must be provided to check the revolving drum, in case the weight of the loop of slack cable should overbalance that of the drum. In this case also a plank brake will come in handy. To Raise from Pit Bottom.—This, like the preceding, is only possible when the clearance in the shaft is sufficiently great to allow of a loaded drum being taken down. The method is rapid but objectionable, in that it amounts, for a period at least, to single suspension, with consequent strains. Lowering by Capstan or Winding Engine requires, perhaps, more care than any of the preceding methods. It should only be undertaken in the case of heavily- armoured cables. Lowering should be continuous and without interruption, to avoid undue bearing strain against the jockey pulley. When winding from the cable drum to engine drum the cable bend should form a C, never an S bend; and when the cable is used for any but the upper- most length in a shaft, great care should be exercised in winding it over the steel hawser and the couplings underneath it. Lowering with Loco.—This method should only be adopted as a last expedient. Before leaving the subject of shaft cables, a word should be said as to the advisability of sharing the total underground load between two or more feeders. With ordinary care, cases should be rare indeed in which both mediums of supply are likely to break down simultaneously. An even greater precaution is to instal mains in separate shafts, making their electrical con- nection below ground. (To be continued.) Hull Coal Exports.— The official return of the exports of coal from Hull for the week ending Tuesday, February 4, 1913, is as follows:—Antwerp,978 tons ; Amsterdam, 1,735; Bombay, 1,121; Bremen, 780; Aalborg, 986; Barcelona, 1,332; Copenhagen, 289; Christiania, 651; Drontheim, 310; Drammen, 1,318 ; Gothenburg, 204; Ghent, 366 ; Hamburg, 3,192; Harlingen, 1,225; Kiel, 1,390; Karachi, 413; Leg- fs. ><•>! A" ; -W- ■1 'I ! A’ .-7-: - . . .. .... ■.■ 1 * ” ’ ’ - ’ t -« ■ ■ i’ . - ' I .,’ .>T'’1 - % •* ' v t ■- 1 .. ’A. V-... ’» ’ -1 ’ ■ ' • ...... > ..v .. > • ■ ■' > :. . ■ ■ Section of the Beresford Seam at Snowdown Colliery. horn, 509; Marseilles, 715; Naples, 1,723; Oxelosund, 3,939; Philippaville, 2,057; Rouen, 4,986; Reval, 2,372 ; Riga, 5,890; Rotterdam, 1,672; Stettin, 1315; Stockholm, 303; Taranto, 4,399; Venice, 4,450; Westerviek, 1,051; total, 51,671 tons. Corresponding period last year, 53,660 tons. Collieries and Income-tax.—The First Division of the Scottish Court of Session has disposed of an appeal for the Darngavil Coal Company Limited against the Surveyor of Taxes, Glasgow. The Lord President said that the case raised the question under the Income-tax Acts of what deduction should be allowed for necessary expenses before striking the profits of a coal company. The deduction claimed was in respect of payments made by the company to a wagon company under a hire and purchase agreement. Hitherto there had been no difficulty in adjusting the matter, because the practice of the Crown had been to split up the payments and allow a deduction of such portion as they thought fairly represented hire; and, on the other hand, they did not allow any deduction for the portion that represented a payment towards eventual purchase. But matters had been altered by a circular which was sent by the Secretary of the Inland Revenue to surveyors of income- tax which practically instructed in very dogmatic terms that no allowance was to be made at all, because all such instalments were merely payments towards purchase. His I lordship thought that it was to be regretted that circulars of that sort should be sent forth without taking the advice of the law officers. There was a sale and purchase agree- ment and also a hiring agreement, and the hire was a proper deductible expense, just as if the coal company had no wagons at all, and simply hired their wagons from day to day. It was equally clear that they could not claim to deduct the whole of what they paid to the wagon company, because a large portion of what they paid was really a payment for an option at a future date to get a wagon at a sum far below its real value. Their lordships had not the material to say what was truly hire and what was truly payment towards an eventual purchase, and the proper course was to remit to the Commissioners, with an instruction that they were bound to allow as a deduction that portion of the ! yearly payment made in respect of those wagon agreements | which represented the consideration paid for being allowed to use a wagon which, under the contract, was not yet their I property. THE BERESFORD SEAM AT THE SNOWDOWN COLLIERY. In our last issue we gave some brief particulars of the opening out of the first seam of coal at the Snowdown Colliery, between Dover and Canterbury. We give herewith a photograph showing a section of the seam in the main road, which is now being driven at a depth of 1,490 ft. from the bottom of No. 3 Pit. The seam, which was named after the late Mr. Beresford Wright, has an over-all thickness of about 6 ft., but fireclay partings reduce the net thickness of coal to just under 5 ft. One of these partings will be seen about 1 ft. from the roof in the photograph, and there are several small bands near the floor which render this portion of the seam less valuable. The best coal is to be found in the portion lying near the roof above the parting already referred to, and in driving this has been left up in the first instance. 1 Above the coal there is a strong roof. So far as can at present be judged, the seam lies practically flat. We give below the full report of Mr. G-eorge R. Hislop on a sample taken from the coal:— A sample of this coal, representing the entire product of the seam, received from the Snowdown Colliery Limited, Nonington, near Dover, on the 20th instant, gave on examination the following results :— Mineralogical Characters. The coal possesses considerable lustre and brownish- black streak; fracture partly defined by organic remains, and partly coarse, angular and crystalline; cross-fracture small cubical, semi-resinoid and crystalline; partly finely columnar between the several lines of stratification, and with shining planes in the natural partings; moderately cohesive and very compact; under heat it intumesces and agglomerates ; coke, silvery ; colour of ash, brown ; thick- ness of seam, 47 inches; mean specific gravity of the coal, 1,276 (water 1,000) ; weight of one cubic foot, 79’75 lb. Chemical Analysis. Volatile matters (containing’44 of sulphur) 29 02 per cent. ( carbon 62’59 ■) Coke consisting of ■; sulphur ’28 >........ 68’94 „ (. ash 6 071 Water expelled at 212 degs. Fahr.......... 2 04 ,, 100-00 „ Practical Results. Gaseous Products. Gas per ton of coal at 60 degs. Fahr. and 30 in. bar....................... 12,465 cubic feet. Gas from one cubic foot of the coal ... 438 43 cubic feet. Specific gravity of the gas ......... 430 (air 1,000). Hydrocarbons absorbed by bromine ... 4'00 percent. Durability of one cubic foot by 5-inch jet flame ......................... 35 min. 12 sec. Value of one cubic foot of gas in sperm 403 2 grains. Value of gas from one ton of coal in sperm................................ 117’98 lb. Illuminating power of gas in standard candles (per No. 2 Met. Burner).... 16’8 candles. Sulphuretted hydrogen (H3 S) in foul gas................................. 100 per cent. Carbonic acid (CO2) in foul gas ......... 3’25 per cent. Carbonic oxide (CO) in foul gas...... 6’25 per cent. Sulphur eliminated with volatile products .............................. 6’27 lb.