June 14, 1918. / THE COLLIERY GUARDIAN. 1197 access to the scaffolds being by means o£ a short chain ladder hooked to the edge of the cylinder. Before putting the cylinder into the shaft, the three guide ropes were firmly gripped and held to the bottom beams of the chief scaffold, then detached from the headgear, and the three ends allowed to hang down the pit. After the cylinder had been built in the shaft, the free ends were brought up the inside of the cylinder, and again attached to the headgear. Before raising the cylinder from the scaffold, all tackle was carefully examined; it was then raised about a foot, and all tackle again examined. The cylinder, which weighed about 6 tons, was again lowered and the brakes thereby tested. This test was again gone through, but this time the weight was raised about 3 ft. On the third trial, the weight was raised about 9 ft., and again lowered to the scaffold. All the tackle was then examined again, and the weight raised about a foot clear off the scaffold. Twelve guide plates, of 18 by 3 by J in. iron, bent inward at the lower end, so that the tube would be guided safely past any abrupt edge of brickwork or temporary woodwork, were now bolted to the bottom of the tube. The top beams of the scaffold were then rolled aside, and the cylinder lowered to the desired place. It was necessary to prepare a scaffold on which to rest the cylinder, and this could only be done by the men going down the inside of the hanging tube. It was found impos- sible to prevent the tube from rotating during its descent, and causing the three guide ropes to be wound round the capstan rope, thus forming a rigid rope of about 4 in. in diameter hang- ing vertically down the shaft. At many places, therefore, owing to the shaft being very much out of place, this rope was very near the side, and not always the same side of the shaft, so that in descending in the kibble, which was necessarily less than 2 ft. in diameter, as it had to pass through the chains which attached the cylinder to the capstan rope, there was not much room to carry tools and timber of any description. Further, when approaching places where the capstan rope was near the side, it was neces- sary to swing the kibble round to the wide side, and to watch carefully that the rope did not twine around the capstan and other ropes. Even with the greatest care, however, this hap- pened more than once, the signal wire too being involved in the tangle. When the scaffold was almost finished, a huge stone, which weighed about 10 tons, fell, but fortunately against a shoulder of the strata near the bottom of the cylinder, and then against the tube, the latter being crushed so that its widest part at the lower end was only 2 ft. 4 in. in diameter. The scaffold, however, was still intact, and as the intention was to cut out the tube after the cavity had been filled with concrete, this could still be as easily done as if it had remained circular. As the cylinder did not now sit concentric with the shaft, in order to bring it back to the vertical, two holes were bored in the hard strata a few yards above its upper end, pins were driven in, and the cylinder attached by means of chains. By straining these chains the cylinder was drawn over to a vertical position. These pins also served to take part of the weight of the cylinder off the scaffold, so that in the event of the latter giving way the cylinder might still be held in position. A platform about 5 ft. in diameter was next erected on standards fixed to the top of the tube, a space of 15 in. being left between the top of the tube and platform for ventilation purposes. The capstan rope having been taken out of the shaft, the guide ropes were put back into their proper position. An iron box with a capacity of a little over a cubic yard was built to take down the concrete. The bottom of the box was simply a good strong door secured by a suitable pin. Shoes were attached to the box for the guide ropes. Two men descended with each load, and the pin was drawn, so that, when the box was raised 8 or 9 ft., the concrete was left on the platform, and could be pushed into the cavity, care being taken to distribute it evenly all the way round. The box was then lowered again, the door fixed, and the box raised to the surface for another load. Sixty trips per 24 hours was found to be a fair day’s work. The concrete used consisted of a mixture of cement, ashes and sand, and broken brick in the proportion of 1,4, and 3 respectively. For every half-dozen loads of concrete, a load of stones was taken down, and these were spread through the concrete. It was thought that if something cheap that would occupy a fair amount of space could be obtained, the strength of the packing would not be impaired, provided the amount of the concrete next the shaft was adequate. For this purpose, all the old grease barrels were gathered and their ends sealed. The barrels were let down gently to the top of the concrete, by an ordi- nary clothes line, part of the line, of course, going with each barrel, which rolled down the inclined surface of concrete, and so away from the side of the shaft. When all the barrels had been used, a fair number of boxes were made for the same purpose. While the concrete was being put in it was considered that if boxes were made of a suitable shape and kept close to the tube, so that that portion which would require widening could be kept clear of concrete, a great deal of time and expense would be saved. Boxes were accordingly made, m || b Bim muni HFig. 1.—Vertical Section of Shaft. but they could not all be kept firmly in position, and so the attempt was not persisted in. After using 480 cu. yds. of concrete, 80 cu. yds. of large stones, and about 20 cu. yds. of old barrels, boxes, etc., the shaft was then fairly safe to a depth of 250 yds. from the surface. For removing the tube, arrangements had been made to have bits cut up by the oxy-acetylene process. Each 8 ft. piece was cut longitudinally into three, making 18 plates each 8 ft. long by 4| ft. wide, for convenience in handling. The cylinder having been removed, the widening of this part of the shaft was commenced by cutting away the concrete to such an extent as to allow the large kibble (about 3 ft. in diameter) to pass straining chains O/d curb cIS Is? Fig. 2.—Vertical Section of Repaired Portion. Temporary scaffo/d /or DUi/diny of cylinders £ I ... Ofc X • . • w . 1 - - 3 7^ • •'S>' ■a: d :/&•< •• it- p Joining of cylinderpartyT^^ Scaffold /ram which cylin were joined together through, and still afford sufficient space for ventilation purposes. This work had to be carried out by pick, hammer and wedge, and was consequently very slow. The necessary repairs below this point were not very serious, and were soon accomplished. Application for exemption from the provisions of the Coal Mines Act, which requires that a cage shall be used for escape pur- poses, was granted, and this allowed the men who had been idle during these operations to resume work. The operation of completing the cutting of the concrete to the finished size of shaft was now resumed, and in a few weeks the cage was running under what was considered to be reasonably safe and reliable conditions. Mr. L. F. Gjers, of Busby Hall, Carlton-in-Cleveland, head of the firm of Messrs. Gjers, Mills #and Company, Ayresome Ironworks, Middlesbrough, who died on Feb- ruary 4, left estate valued at £286,420. gross. Arrangements have been made (subject to the necessary resolutions being passed and the sanction of the Court being obtained) for the amalgamation of the two well- known engineering businesses of Ruston, Proctor and Company Limited of Grantham, and Richard Hornsby and Sons Limited, of Grantham. .Coal Controller on Fuel Rations.—Sir Guy Calthrop (Coal Controller), in an address on the aims and objects of the new Household Fuel and Lighting Order in London, in Friday, said a quarter of coal previously available for domestic use must now be saved. A household might take the fuel it required either as gas or coal or electricity. The method was to fix fuel values in ton equivalents, and 15,000 cu. ft. of gas or 800 Board of Trade units of electricity had been taken as the equivalent of one ton of fuel. It was not desired to restrict the consumption of gas, owing to by-products. In some districts it was not possible to manufacture gas to meet demands, and the gas allowed per ton of fuel might be 12,000 cu. ft. In other districts it might be desirable to stimulate the con- sumption of gas and increase the allowance to 18,000 cu. ft. The shortage of coal was due to the withdrawal of 75,000 skilled miners, or a reduction in output of 29,000,000 tons of coal. The reason for drawing a line from the Wash to the West of England was that in the south the question was how much coal they could get into the works, and in the north how much they could get into the grates. LETTERS TO THE EDITORS. The Editors are not responsible either for the statements made, or the opinions expressed by correspondents. All communications must be authenticated by the name and address of the sender, whether for publication or not. No notice can be taken of anonymous communications. As replies to questions are only given by way of published answers to correspondents, and not by letter, stamped addressed envelopes are not required to be sent. MAGNETIC DECLINATION. Sirs,—I have read the letter in your last issue of the 7th inst., and this subject of declination is of great importance to underground surveyors in this country. It is quite feasible to lay out a colliery by other means than the magnetic needle, but that colliery must preferably be a new mine, and where the surveyor can have the facilities which are not always granted at most collieries, although it means little more in cost and is in accuracy much more certain and correct. When I was in the gold mines in West Africa, all the mining surveying was done by hanging two piano wire lines in shafts, the bearing of which lines was known from a true north and south line on the surface. I performed much accurate work there, especially in rising shafts to meet sink- ing shafts, of no mean expenditure. There are so many points to watch in the correct keeping of mine plans that I am surprised a man can be allowed to qualify as a inine surveyor who has had only two years’ experience, as required by the 1911 Act. And again, in this examination for surveyors’ certificates there is no practical work to be gone through. Even in one of our latest Colonies (Northern Nigeria) a surveyor must pass a stiff exam, and prove his abilities as both a practical and a theo- retical man. John Rhodes, M.Inst.Min.E. Ilkeston, June 11, 1918. Sirs,—I should like to endorse the apprecia- tion and comment in your issue of the 7th inst. re magnetic declination, and I hope the publication of these will arouse colliery surveyors to a sense of re- sponsibility, and also that colliery companies will appreciate those surveyors who by their example are discarding the magnetic meridian in the correlation of their surveys. It is certainly not to the credit of surveyors in this country to adopt methods which in other countries are condemned on account of inaccuracies. I am of opinion that the publication of these tables ably refutes the argument of those who allege a “yard or two does not matter,” and gives additional justification to those surveyors who have turned their backs on the magnetic meridian in the correlation of their surveys. G. Reynolds, Surveyor. Snowdown Colliery, Nonington, near Dover. June 12, 1918. THE AMERICAN COAL TRADE. During “ Coal Week”—June 3 to June 8—the Fuel Administration made special efforts to induce con- sumers to order their coal early,- so that, by deliveries being made in summer, transportation conditions would be correspondingly eased next winter. The Coal Age (May 18) states that coal production is barely keeping pace with the demand for fuel needed for immediate consumption. Some few plants here and there are accumulating reserve stocks, but a lack of sufficient storage space will prevent many from laying in much larger supplies. Anthracite production is now at its maximum. The April shipments amounted to 6,368,372 tons, an increase of 776,074 tons over the corresponding month of 1917. Increased demands absorbed the entire output, and no reserve stocks of any consequence remain in the hands of dealers. To further restrict the consumption of hard coal to those sections of the country where it is more urgently needed, no anthracite will be permitted to move west of the Mississippi River or into the South. The greatest factor limiting production is the old one of inadequate car supply. Labour trouble in one Penn- sylvania district further serves to diminish output, while in Alabama, where the car situation is fairly good, the miners refuse to work full time through inherent laziness more than anything else. Regarding the price of railroad fuel, this question remains unsettled. The railroads are buying coal on a hand-to-mouth basis, and refuse to enter into contracts. The necessity of keeping American industry going at high speed with the supply of coal that will be avail- able this year has led to the inauguration by the Fuel Administration of a fuel conservation movement in industrial power plants. By the correction of firing and operating methods in industrial plants, Dr. Garfield hopes to save at least 25,000,000 tons of coal. Each power plant is to be inspected by engineers appointed by the Fuel Administration. Boston reports states that many industries cannot obtain sufficient fuel. At Hampton Roads supplies exceed tonnage. Anthracite shipments in the Phila- delphia area are unsatisfactory. A great deal of under- sized coal is coming on the market. The supply of bituminous coal in Baltimore is considerably better than for some time past. Little improvement in car supplies is experienced at the Pittsburg district mines, but they are increasing slowly in the Connellsville district. Very little Connellsville coke is finding its way to the open market, shipments being readily absorbed by con- tracts. Some of these are at flat prices, averaging about 8 dols. 25 c., while some are based on the pre- vailing market and thus are settled at the Government price. The market remains quotable at the Government limits: Furnace, 6 dols.; foundry, 72-hour selected, 7 dols.; crushed, over ] -in., 7 dols. 30 c. per net ton at ovens.