April 9, 1915. THE COLLIERY GUARDIAN. 753 100,000, while in a number of other cases the effluents contained much suspended matter, and were classed as bad. At the time Dr. Wilson’s report was written there were 45 sets of coal washing plants in use in the West Riding. In 21 instances there was no direct discharge to the stream, the water being re-used. Another set of figures, given in Wilson and Calvert’s “ Trade Waste Waters” (p. 21), may also be quoted here :— Analyses of 12 Samples of Coal-washing Water after Treatment. Suspended solids..... 2’8 (range 0*8 - 5’7) Soluble solids ...... 392’7 (range 178’0—950 0) In Lanarkshire, in 1909, out of 71 collieries provided with coal washing plant, 67 were also provided with settling ponds, and the effluent was re-used in 64 cases. (Second Report on the Administration of the Rivers Pollution Prevention Acts by Dr. J. T. Wilson, 1909.) In Durham and Lancashire similar measures are taken for removing suspended matter from the washing water, but in South Wales a good deal of fine coal still finds its way into the streams. The late Dr. W. Williams, medical officer of health to the Glamorgan County Council, stated in evidence before the Commission (January 27, 1909) that only some 12 or 18 colliery owners in his district had been induced to construct settling tanks or ponds. The efficiency of settling tanks depends mainly upon their capacity in relation to the volume of liquid dealt with, and since coal washing water contains a very large quantity of suspended matter, it follows that frequent- cleansing of the tanks is necessary, unless their capacity is very large in proportion to the flow. In this connec- tion it may be useful to give the analytical figures relating to some average samples drawn at a colliery in South Wales. Large settling ponds are provided at this colliery, but at the time of sampling their capacity was much reduced by the solid matter which had settled in them. Incidentally the analyses showed how slightly the water itself may be iafiected by coal washing. No. 155.—Crude < oal-washing water.* No. 15 Partially-settled coal- washing water.* Original sample. Paper-filtered sample. Original sample. Paper-filtered sample. Parts per 100,000 Ammoniacal nitrogen Albuminoid nitrogen Total organic nitrogen Nitrous nitrogen Nitric nitrogen Total nitrogen, by Kjeldahl “ Oxygen absorbed” from N'8 permanganate at 27 degs. Cent. (80 degs. Fahr.) at once ... “Oxygen absorbed” from N/8 permanganate at 27 degs. Cent. (80 degs. Fahr.) in 4 hours Chlorine Hardness by soap test, expressed as carbonate of lime (CaCO3) Solids in suspension Solids in solution 9’08 D059’6 $653’2 V’+ t!059 6 £406.4 Nt 0’038 0’022 0 032 0’0 0’11 0’18 0’20 0’50 1’52 7’35 40-6 f 3’6 V’ 40 6 (37 0N. 2 39 Q04’8 £ §80’0 V. b 1124’8 N. 0’038 0’007 0-6 0’09 0’09 0’09 0’54 1’55 9’82 40’0 f 4’° V’ 400 (36’0 N. * Average of five samples, taken in equal quantities every hour from 7.30 a.m. to 11.30 a.m. Drawn December 16, 1909; analysed January 19, 1910. f 68’4 of this came down in the Gooch filtrate on adding four drops of nitric acid and allowing to stand for about 24 hours. Of this, 13’6 was volatile. J “ V” = Volatile on ignition; “ N” = non-volatile on ignition. § 53’2 of this came down in the Gooch filtrate on adding three drops of nitric acid, and allowing to stand about 24 hours. Of this 9’2 was volatile. Notes on Samples when Analysed.—No. 155: Black opaque liquid with no smell. Some of the solid matter was extraordinarily fine. The paper-filtered liquid (through Swedish paper) was fairly clear, with brownish opalescence. It deposited, however, an appreciable precipitate on standing. No. 156: Brown-black in appearance, 'with much extremely fine suspended solids. No smell. The paper filtrate (through Swedish paper) was nearly clear, with a faint dark opalescence. It deposited very little solid on keeping. The Commission also refer to the evidence given on October 26, 1909, by Mr. Percy C. Greaves and Mr. Roslyn Holiday, on behalf of the Mining Association of Great Britain. As regards coal washing water, Mr. Greaves said :—“ The effluent can be fairly easily dealt with, either by means of settling tanks or by passing the water through washed coal, and mixing the ‘ slimes ’ with the small coal for coking, and this is done at prac- tically all the collieries I am connected with.” As regards (a) coal washing water, (b) coke quenching water, and (c) water from blowing oft boilers, Mr. Holiday said : “ The solids in suspension in these effluents can be dealt with at a not excessive cost by means of settling tanks, or in the case of (a) by passing the water through washed coal. In confined areas, where the land is flat, the settling tank treatment is considerably higher in cost.” The Commission have had no experience of the plan of filtering through small coal mentioned iby these two witnesses. At a colliery in Lanarkshire the Commission saw a third method of disposal, which appeared to be very effective. At this colliery the washing water is passed through settling tanks for the recovery of the larger particles of fine coal, and the partially clarified liquid is then pumped into large and deep excavations cut in a heap of waste shale. The water can only find its way out of these excavations by percolating through the shale, and it is thus filtered as well as settled before finding its way to the river. "When one excavation becomes full of liquid, it is left to drain, and another is used. At collieries where the fine coal is very dirty, and where the washing plant is situated near a heap of fairly loose shale, the above plan would seem to be an admir- able one. At the same time, it should be noted that ferruginous drainings might issue from the heap after a little time if the shale contained much pyrites. From the results obtained in the West Riding of Yorkshire and elsewhere, it is clearly evident that coal washing water can be effectively dealt with by settle- ment in tanks or ponds. In most cases some of the fine coal settled out of the washing water has a com- mercial value. In the colliery districts of Yorkshire, Lancashire, Durham, and Lanarkshire the settled waters are frequently used over again, to the advantage of the coal owner. Dr. Maclean Wilson’s analytical figures and enquiries and observations lead the Commission to believe that reduction of the suspended solids to four parts is quite practicable at a number of collieries. At some collieries, where the coal is mixed with a good deal of clayey matter, there may be difficulty in reducing the suspended matter to such figures without the use of a coagulant. (To be continued.) Rainfall. Statistics.—Messrs. John Davis and Son (Derby) Limited, All Saints Works, Derby, supply us with the following particulars of rainfall :— Derby. Duffield. Average for Derby 1884-1904 inclusive. In. No. of rainy days. t In. No. of rainy days. January ... 2-97 ... 21 ... 3’18 ... 18 ... 2T3 February ..., ... 2’41 ... 16 ... 3’36 ... 18 ... 1’57 March ... 1’00 ... 14 ... 0’91 ... 12 ... 1’67 — — ■ ■ Total ..., ... 6’38 ... 51 ... 7’45 ... 48 ... 5’37 Rescue Work at an American Explosion.—The specially equipped rescue car that the Federal Government has in West Virginia was stationed at Glenalum when news came that 160 men were entombed at Layland. Immediately the information was telephoned to the Norfolk and Western agent, and within 10 minutes an engine was coupled and the car headed for Williamson, where another and better engine was waiting to continue the journey to Kenova, and there the second largest passenger engine in the country stood waiting to make a record run in the hope that the lives of some of the men might be saved. Inside of the car cylinders were being charged and apparatus assembled so that immediately upon arrival at the mine the car crew were ready to go in any direction that useful information might be obtained. Each member of the crew has his own set of “ Proto ” apparatus, made by Messrs Siebe, Gorman and Company. The canary that is used to detect the white- damp died within 100 ft. after leaving fresh air. By the use of their apparatus the crew were enabled to toil all night, climbing over falls and crawling through holes or through low rooms so that the air men might know in just what direction to work. The next morning a team of rescue men from the United States Coal and Coke Company, Gary, W. Va., stood ready to relieve them. Their work was dropped and 11 men immediately despatched to the scene of the disaster. Here they toiled, five men in each crew, and a fresh crew at work every six hours, while the State inspectors and the brattice men built brattices to force the air through the deserted entries to enable them to carry out the dead. At the end of four days and nights over 100 dead men had been carried from the mine and two thirds of the underground (area had been explored. That evening the rescue crew had made an exceptionally long run and found a section where force of the explosion was less evident. Then live men were suggested. The fan was stopped to change it from blowing to suction in order that they might the sooner get in the other part of the mine. "While doing this, five men who had been trying every six hours to get out during the past four days, were able to get through. Immediately the apparatus men started in that direction and after travelling more than a mile with the apparatus, they were able to rescue 42 live men who had bratticed themselves off to keep the foul air from getting to them. THE SOUTH WALES COALFIELD: PART III/ By Henry K. Jordan, F.G.S. (Continued from page 705.) Mr. Jordan gives a valuable series of vertical sections which cannot here be reproduced. The following interesting details respecting these sections are abstracted from Mr. Jordan’s paper :— Blaen-hirwaun Colliery, Tumble.—This colliery is interesting as being, so far as the author is aware, the only deep pit that has been sunk to the Big Vein in the Gwendraeth district, and it therefore gives details of the strata which are not otherwise obtainable. The coal at 113 yards 2 ft. 4 in. appears to be the Felin-isaf, and the seam at 90 yards 2 in.—50 yards over the Big Vein—may be the coal to which Mr. Thomas Arnold referred in bis discussion of Part II. as being 60 yards above the Big Vein at Tumble. The seam 90 yards above the Big Vein is reported to be 2 ft. 6 in. thick and of good quality. It does not appear to have been recognised in the Gwendraeth Valley at Pouty- berem and Pont-Henry, but it is shown in the horizontal section at its correct horizon so that it may be searched for. For the section of this pit the writer’s thanks are due to Mr. John Lewis, the manager of the colliery. Garngoch No. 1 Colliery.—This colliery is situated about 11 mile to the north-east of Gowerton Station of the Great Western Bailway and the pit reached the Swansea Six-feet seam in March 1914. The Six-feet seam proved to be of excellent thickness and, on the whole, the section agrees fairly well with the Gorseinon Colliery section. The distance between the Swansea Six-feet and Three-feet seams is, however, about 12 yards less at Garncoch than at Gorseinon, being 10 yards 2 ft. 9 in. at the former and 23 yards at the latter. Gwaun-cae-gurwen Colliery, East Pit. — Near the north-west corner of Glamorganshire the East pit of the Gwaun cae-gurwen Colliery Company has been sunk since the publication of Part [I. in 1910. Its site is 1,620 yards E. 8 N. of the “ Old Pit ” of this company. The East pit—for the section of which the writer is indebted to Mr. Fred Hargreaves—intersected 300 yards of strata to the Big, or Stanllyd Vein, which is con- siderably in excess of any sinking to that vein in Carmarthenshire, and has only been exceeded in this part of Glamorganshire by the Tareni pit, near, Pontardawe, which is described in Part II. The Swansea Valley.—The Primrose Colliery Company has recently drifted to the north-west from the Big Vein to the Brass, or Peacock, Vein at their Taieni Colliery, which is situated on the east side of the Biver Tawe, about 2 miles to the north of Pontardawe. The Brass Vein is estimated to be 45 yards beneath the Big, but the measures in the drift were found to be much disturbed near the Tawe Biver, thus interfering with a correct measurement. The estimated distance is in excess of that proved in Ystradgynlais district, 2 miles or so to the north, and also greater than the Brynamman distance. In the past an opinion was held that a fault ran down the valley past Yn\ s-y-geinon and the Tareni Colliery position, and the colliery disturbance just mentioned lends support to that view, but if there be a fault it must be of somewhat small throw, for the Bed Vein has been proved by pits on either side of the valley near Ynys-y-geinon Junction of the Midland Bailway, at depths which are incompatible with the existence of a big fault. The Primrose Colliery Company has also recently put down a bore- hole on the west side of the Tawe in order to prove the depth to the solid, and thus ascertain if it were a suitable site for a new pit. The borehole started at a point 153 ft. above mean sea-level, and was carried to a depth of 225 ft. without reaching the solid, and was then stopped, the lowest bed being boulders. These figures show the bottom of the borehole to be 72 ft. below mean sea-level, and the solid, or undisturbed rock to be at a farther and unknown depth, and that a rock basin must exist at this position, which is about 11 miles from the sea. How far up and down the valley this jock basin extends cannot be stated, but at Gueret’s Colliery, near Clydach—about 5 miles nearer to the sea—the solid was reached about 30 ft. above mean sea-level, and this position, also, is near the centre of the valley on the west side of the Biver Tawe. Thus the erosion of the valley has been 100 ft. greater at the borehole site than at Clydach, and if the rock basin had not been filled with glacial drift the depth of water in it . would have exceeded 100 ft., or more than sufficient to safely float our biggest Dreadnoughts. Lower down the valley the erosion has been still greater, as at Pentre, near Lan dore, gravel exists for at least 150 ft. beneath mean sea-level, as the workings in the Hughes Seam got into gravel at that depth. Neath District.—The existence of a large and unknown fault under the town of Neath and running southward past Eaglesbush Colliery has recently been proved by the investigations and measurements of Mr. B. Vaughan Price, a member of this institute and general manager of the Main Collieries, near Neath. When at these collieries in August last, Mr. Price—who is probably the greatest authority upon the C( al measures "of that district—laid before the writer various facts and measurements upon which his conclusions were based, in all of which the writer fully concurs. The measurements and clearly reasoned conclusions of Mr. Yaughan Price prove not only that the fault has a throw of 170 yards down to the west, but that its position near Court-Sart Pit must be to the east of that pit, also that the mouth of the Eaglesbush water-level and the adjacent quarries show that the fault must be to the yvest of those * Abridged from a paper read before . the South Wales Institute of Engineers, and published in the Proceedings.