The Birmingham age-herald., 1912-06-13

 average time. While we watched 1t op- crate the machine made a cut of two yards in eight minutes It pulls itself along the face by a wire rope and is operated by three men; one places props after the machine, one attends to the hose, and. the other works the machine Tn many of the long wall mines no min ing machines are used. the small amount of undercutting being done by hand As a general proposition, in long wall work, there is more or less weight on the coal. which reduces very largely the amount of hand work or shooting necessary in breaking down.
 At another Scotch mine chain drag conveyor. operating along the face in long wall. was examined The coal is shoveled into the conveyor, in all types, and is dragged to the end where 1t discharges into the mine cars. This eonveyor has averaged 120 tons daily for a years work, single shift. One of the Scotch managers informed us that he did not think a conveyor would save anything over cars in seam or coal three feet thick or more, but We saw conveyors on the continent working in l thicker veins. He said his company had | Just closed a mine down because 1t did not pay, where the seam Is only II
  pay. Where this chain conveyor is used the coal Is shot from the solid; the conveyor being protected by timber placed over It. Mining machines were formerly used, but were taken out on account of bad roof. The 300 foot con- veyor is moved up to the face. three feet per day, average, by sylvester jac cks three men doing the work on the night shift. The filling of an eight hundred weight car by the conveyor took II seconds
 We visited a Welsh mine in the Car diff section. where six foot seam 1900 feet below the surface, was being worked longwall with stall roads 13 yards centers and headings cutting faces every 60 yards. The coal is of very superior quality and is supplied largely to vessels at Cardiff Only the round coal is recovered. the slack being kept in the mine, and even then 25 per cent passes through the screens IS slack. The miners use large scoops, without handles, for loading the coal, Into which they scrape the Jumps, while on their knees. with their hands.
 At another Welsh mine we examined the working of 1o-foot seam on the longwall system and which had been changed from pillar and stall. The man agement stated under the longwall sys- tenn the cost had been cut 1 shilling per ton. Thirty per cent of the coal was lost with pillar and stall but the longwall method had cut this to 10 per cent. The longwall system gets 5 per cent more | large coal than under the old plan-
 Process in Germany
 Near Essen. Germany. we examined a mine working a seam of coal about 40 inches thick, with a good top. and dip ping considerably. The longwall sys- l tenn is used, the gateways are kept well ahead and the bottom rock is shot up and | used in the packs; the work being done 1 in sections of about 800 feet. The face l of the work is usually kept IS to 30 feet | ahead of the packing. if the roof will allow it. As the coal is removed packs are built and sand flushed in. course sand of loamy material is used and is derived from deposits on the surface, and within 300 yards of the shaft. The flush I ing is done to protect the company's steel | works
 | Tn upper Silesia we visited a mine working a 72-foot seam in five sections or slices, starting from the bottom up. l The ribs are whitewashed in order that sloughing may be easily observed. and to prevent miners taking coal from the pillars. The flushing system is in opera tion, using sand from the surface pits nearby. The sand is hauled in 12 cubic feet cars, dumping in mixing pit, and, after screening, washed into pipes which | carry it to the workings The plant handles 25O0 cubic yards daily in two 10- l hour shifts. The mixing is one of water l to one of sand in volume The cars are steel side dump affairs. with hopped bot toms. running lengthwise. and grate bars l underneath on which fire is built in cold weather to keep the sand from freez- l ing.
 ''The use of mine timber in European practice is generally very systematic. h some countries the laws compel its use l at stated intervals. regardless of the na- ture or condition of the mine
 sAt German mine we found the shafts I lined with cast iron segments or tubing in the upper portions to keep out the water with brick lower down. The sink ing went through 162 feet of quick sand and to do the work successfully the freez- ing process was adopted requiring B holes drilled In circle considerably larger than the diameter of the shaft through which the freezing liquid wal passed.
 The concentration process of sinking
 where great quantity of water mus
 be dealt with. is preferred by many as I permently shuts off the water from ths
 shaft, and renders the use of heavy lin I ing unnecessary"
 On Mine Tracks
 Model Mine Track" by J. B. Mcintyre
 was the last address. He said in part:
 ''Grantng that proper plan of de
 velopment and correct mining methods
 are of first importance in coal mining
 an effective method of transportation oi
 the output to the surface is of equal
 or is at least next in order of value if
 reducing to minimum. the cost of coa
 f. o. h. cars for shipment. Precedent thef to securing such minimum cost. the
 movement of the carrying vehicles mus be made with regularity and speed. theil
 capacity must be as great and the mum
 ber in train as many as the mining con
 ditions allow; and the motive power units
 or locomotives must be of sufficient power to handle such trains on gradients
 which the engineer of the mine develop
 ment will plan to keep at as low rates
 as contour of the coal will allow. Under an effective working system o transportation the rooms will be regu larly served the gathering motors ana the main haulage motors made trips witt
 regularity and dispatch. enabling the If at the shaft or slope and the screening
 and loading at the tipple to be done witt
 uniformity and at maximum capacity. While for main haulage-way leadin' out from the mine mouth which may re main in service for many years or dur ing the life of the mine. and over whiel l all the output passes, and is hauled D, the heavy motors. 1t may be allowable L use rail even of larger section than an. , formula requires. substantial track tim 1 Der treated and tie plated. ballasted wit } selected material even tv extent of bring ing in furnace slag for the purpose fully and solidlv tanned. such. expens