THE COLLIERY GUARDIAN. June 21, 1918. 1256 ____________________________________________________________________________________________________________ ______________________________________________________________________ years of few sun spots. For this reason some meteorologists have been led to associate magnetic storms with sun spots, and hence to expect that they would recur at regular intervals of about 27 days, corresponding to the apparent rotation period of the sun. This 27-day period is not easy to estab- lish, because there is no exact definition of what amount of disturbance constitutes a magnetic storm. Dr. Chree, however, has carefully analysed the disturbance figures between the years 1906 and 1916, and his results do certainly tend to confirm some sort of repetition theory, both for storms and quiet conditions, but he is unable to establish a periodicity of 26 to 28 days any further than to show that there is more than an average chance that after a dis- turbed day there will be another day of more than normal disturbance at about the above interval of time. But there is nothing like a certainty of a repetition. Possibly, as observation is extended, it may become possible to establish a law of recurrence which will make an accurate forecast possible. In the meantime there are certain facts with regard to diurnal variations which may prove to be of practical use in mine surveying. These daily changes are not regular throughout the year. They are greatest in the summer months and least in the winter. The declination, also, is generally nearest the mean value in the period between 5 o’clock in the evening and 4 o’clock in the morning, during which hours it would, therefore, be advisable to conduct underground surveys of more than ordinary importance. In a paper read by Mr. G. Spencer, a few days ago, before the Midland Institute, he gave a graphic illustration of the practical effect of plotting a survey in the early afternoon from a test line of which the bearing was taken at nine o’clock in the morning. He found that this might entail an error of 10 min. or 12 min., which in a distance of 2,000 yds. would mean a deviation of 6 yds. This is merely an illustration of the amount of error that might be caused by ignoring the ordinary diurnal variation of the compass. It might be far greater in the case of a magnetic storm. Mr. Spencer suggests that where greater accuracy is required, surveys should be corrected by the weekly tables published in these columns. In regard to this quest on of correction, however, it must be remembered that the magnetic meridian must not be held responsible for every error in a survey. There is no common agreement as to the degree of accuracy that ought to be demanded. There are many factors to be considered. An error in bearing of 1 min. would mean a deviation of 0 03 ft. a hundred feet away. Dr. Chree also reminded surveyors that there is abundant room for research work in terrestrial magnetism. Hitherto, little attention has been given to records of magnetic changes and electrical earth currents at large depths underground. For this purpose, it is desirable to obtain magnetograph records in mines for comparison with those obtained at the surface. In this connection, attention should be paid to the possible relation between local magnetic disturbance and geological structure, in regard to which Dr. A. Hubert Cox has recently been carrying out some observations on behalf of the Conjoint Board of Scientific Studies. The area selected was in the neighbourhood of Melton Mowbray, and his results tend to show that local magnetic disturbances in that district are related to faults which may possibly be associated with intru- sions of dolerites, which are rocks of high magnetic influence. Although the immediate object of these researches was to elucidate the relation between local magnetic disturbances, and tectonic underground structure, the known occurrence of dolerite intrusions in the coal measures of this country indicates yet another source of possible error in compass bearings in coal mines. We do not know how far mine surveyors take into account this question of local disturbances; but the elaborate magnetic survey of Messrs. Bucker and Thorpe, carried out between 1886 and 1891 throughout the British Isles, show the great importance of this factor. We are accus- tomed to regard the isogonals as smooth curves; but these are merely a compromise for rather irregular lines, the local variations of which add still further to the vagueness of the magnetic meridian. THE COAL AND IRON TRADES. Thursday, June 20. _________________________________________ Scotland. -Western District. COAL. There is nothing fresh to report in the Scotch coal trade. The predominating feature is the scarcity of fuel, con- sumers in many instances only getting day-to-day supplies. In the west of Scotland a fair turnover is being done in export business, mostly for France and Italy, very few neutral licences being granted. Home requirements are as heavy as ever, both for industrial and household use. The output of all classes of coal is fully taken up. Shipments for the week amounted to 99,164 tons, compared with 118,966 in the preceding week, and 121,024 tons in the same week last year. Prices f.o.b. Glasgow. Steam coal.............. Ell .................... Splint.................. Treble nuts ............ Double do............... Single do______.............. Current prices. 27/6 26/6-28/ 28/ -30/ 23/ 22/ I 21/ L’st week’s I prices. 27/6 26/6-28/ 28/ -30/ 23/ 22/ : 21/ Last year’s prices. 17/6-19/6 18 6-20/ 21/ -26/ 23/6 22/ 20/ supplies for neutrals is not likely to be relieved over any part of that period, unless some much more satisfactory scheme of release of miners from the Army is resorted to. The Swedish State Railways turned down the tenders recently sent in for the supply of 35,000 tons of steam coals, offered on the basis of 60s., plus 5 per cent, for merchants’ profit, for large, and 35s. for smalls, which latter were to be taken to the extent of 25 per cent, of the total. The Department is said t > have decided to wait until coals are cheaper, but there is a suspicion that the Swedes may seek to obtain their supplies from Germany. Seemingly, the Nowegian State Railways are not daunted by the highness of current quotations, for their usual bi-monthly enquiry for 16,000 tons of Northumberland, Durham, Scottish and/or Yorkshire steam coals is once more in circulation, this time for shipment over August and September. Tenders are due in on Monday next, and are likely to be based on 65s. per ton for D.C.B. quality, and from 35s. to 40s. for one-fourth smalls. Prices f.o.b. for prompt shipment. __________________________ Tar Fuel for Diesel Engines.—The Hamburger Grund- wasserwerke are using tar successfully instead of tar oil as fuel for Diesel engines driving rotary water pumps delivering 1,100 to 1,200 cu. m. per hour against a 12-5 m. head. Trouble was formerly experienced by coke, etc., in the tar clogging the atomiser and needle valve, and so damaging the seating of the exhaust valves that they had to be changed every ten days. This difficulty was overcome by using a gravel filter. Steam Production with Pulverised Coal.—The economy attained by using pulverised coal for steam raising in boilers is recorded in the results secured in a 24-hour test of 150 horse-power Brownell horizontal return tubular boiler at the demonstrating plant of the Powdered Coal Engineering and Equipment Company, Chicago. Charts are reproduced giving the horse-power developed, flue gas temperatures, water level and gauge pressures, also C02 records and tables giving data of the coal consumption. Attention is particularly drawn to the fact that the C02 content in the flue is considerably higher than in average of . standard practice, and the chart is considered to be quite abnormal in comparison with the records hitherto obtained in steam boiler practice over such a long period of time. IRON. Conditions in the Scotch iron trade show little variation from week to week. Works are so much taken up with war work that makers have little time for anything else. In fact, it is practically impossible to obtain delivery of ordinary mercantile supplies without months of delay, if at all. In pig iron producers are faced with an accumula- tion of arrears. Haematite is absorbed in production, and with the majority of furnaces now producing this material, supplies of other qualities are very scarce. Foundry iron is exceptionally tight, and forge is none too plentiful. Exports are more or less a thing of the past. Nevertheless values remain on a high level, about the following figures: — Monkland and Carnbroe f.a.s. at Glasgow, Nos. 1, 140s., Nos. 3, 135s.; Govan, No. 1, 135s., No. 3, 130s.; Clyde, Summer- lee, Calder and Langloan, Nos. 1, 150s., Nos. 3, 145s.; Eglinton at Ardrossan or Troon and Dalmellington at Ayr, Nos. 1, 145s., Nos. 3, 135s.; Glengarnock at Ardrossan, No. 1, 140s., No. 3, 135s.; Shotts at Leith, No. 1, 150s., No. 3, 145s. p^r ton. Malleable iron makers have a large demand at present for large sized bars, while their steel departments are busy with light rails and other sections on national account, and in rolling steel discard quality. Tube makers have plenty of orders for all classes of tubes. Structural engineers are well booked up, and orders for light castings are quite plentiful. _________________ Scotland.—Eastern District. COAL. Collieries in the Lothians are doing a good business in neutral shipments at advantageous prices. Local demands and Admiralty requirements provide a considerable outlet, and, generally speaking, outputs are insufficient. Ship- ments were 18,054 tons, against 15,975 in the preceding week, and 18,964 tons in the same week last year. Prices f.o.b Leith. Best screened steam coal... Secondary qualities..... Treble nuts ............ Double do.............__ Single do............... Current L’st week’s Last year’s prices. prices. prices 26/6 26/6 20/ 25/6 25/6 18/ 23/ 23/ 22/ 22/ 22/ 20/ 21/ 21/ 19/. As in the Lothians, the Fifeshire collieries are booking a fair amount of neutral business at high rates. Navigations and steams are particularly heavily booked, while small stuffs are coming in for their share. Shipments were 45,659 tons, against 23,599 in the preceding week, and 28,445 tons in the same week last year. Prices f.o.b. Methil or Burntisland. Current prices. L’st week’s Last year’s prices. prices. Best screened navigation coal 29/ -31/ 29/ -31/ 27/6 Unscreened do 24/ -25/ 24/ -25/ 23/6 First-class steam coal 28/ 28/ 23/ Third-class do 24/ 24/ 19/ Treble nuts 23/ 23/ 24/ Double do 22/ 22/ 22/ Single do 21/ 21/ 20/ The prices quoted only apply to French and Italian business ; for all other orders 2s. 6d., or more, per ton must be added, with the exception of secondary qualities Lothian large coal. ________ _______ Northumberland, Durham and Cleveland. N ewcastle-on-Ty ne. COAL. There has not been the slightest sign of yielding in the firm inflation of employment at the collieries of Northum- berland and Durham during the past week. All have been engaged at their maximum capacity of output in the pro- duction of coal to meet Admiralty, Allied and inland needs, a task which has been rendered more difficult than it would have been formerly by reason of the depletion of mining man-power. So great is the request on these accounts, that the miners have been asked to forego their usual Pace holidays next week, and have been offered bonuses for doing so. Under the circumstances, knowing the urgency of the military need of fuel, it will probably be found that it was hardly necessary to offer these pecuniary inducements, for the men fully recognise the gravity of the situation, and only a very small percentage are likely to absent them- selves for any portion of the week, dear though this particular holiday is to the northern miner. Neutrals are vainly clamouring for supplies, and willingly offer the top prices at present quoted in the market. Much as the coal owners would like to do business at these figures, they are having to be content with the much lower scheduled prices which obtain for official and home supplies, and exceedingly little coal is being shipped to neutral destinations at present. The present briskness of employment of the pits, to meet the requirements already detailed, is likely to continue for many weeks to come, and the dearth of I Current Steam coals :— | prices. Best, Blyths (D.C.B.) 30/ -65/ Do. Tynes (Bowers,&c.) 29/6-60/ Secondary, Blyths ....i 25/6—55/ Do. Tynes (Hastings'; or West Hartleys) ...• 27/ -55' O'nscreened ........ .. 23/6 -40 / Small, Blyths ......___20/ -40/ Do. Tynes..........j 18/6-35/ Do. specials ..... ..; 20/6-40/ Other sorts:— ! Smithies...........____ 25/ -40/ Best gas coals (New! Pelton or Holmside) j 25/ -45/ Secondary gas coals' (Pelaw Mainor similar)’ 23/6-35/ Special gas coals ...... 26/6-45/ Unscreened bunkers, | Durhams: 26/6-40 Do. do. ! Northumbrians 26,6-40/ L’st week’s Last year’s prices. prices. 30/ -65/ ; 30/ 28/ -30/ ; 221 -23/ ! 22/6-23/ Coking coals........ 241 -40/ Do. smalls ....i 24/ -40/ House coals ..........; 28/6-60/ Coke, foundry .......... 42/6-45/ Do. blast-furnace......I 42/6-45/ Do. gas ..............; 35/ -40/ .. 29/6-60/ 25/6-55/ 27/ -55/ 23 6-40/ 20/ -40/ 18/6-35/ 20/6-40/ 25/ -40/ j 25/ -45/ j 23/6-35/ i 26,6-45/ I i 26/6-40/ 26/6 -40/ 24/ -40/ 24/ -40/ 28/6-60/ 42/6-50/ 42/6 -50/ 35/ -40/ ; 18/ -20/ ! 13/ i 16/ -17/ 19/ -20/ 21/ 25/ -26/ | 17/6-19/ I 30/ -31/ j 16 6-19/ ; 18/ -20/ ! 18/ -20/ 16/ -18/ ' 27/6-30/ ; 40/ -42,6 i 40/ I 30/ -321 Sunderland. COAL. The strong demands on the coal maiket continue, but only a small business is actually passing, merchants finding it almost impossible to secure supplies. The prospects incline to still greater stringency. Official requisitioning of coal is still extensive, and consequently, with a much reduced output, no supplies are available on the open market. A fair trade is passing in bunkers, and any good brand for neutral buyers is held for 49s., whilst for specials 50s is asked. Manufacturing fuel is earmarked for Admi- ralty and inland requirements. Coke supplies are limited to small parcels. Buyers are numerous, 50s. being quoted for both patent and beehive makes. Middlesbrough-on-Tees. COAL. There is a very great scarcity of fuel. Output of coal is practically absorbed officially in various directions, and supplies are all but unobtainable for any outside business. Any such transactions are for long distances ahead. Inflated prices continue to be named for neutral shipment, yet where business is possible they are eagerly entertained. For Durham gas coal quotations range from 35s. to 50s., and similar rates rule for manufacturing fuel; whilst up to as much as 50s. is named for best Durham bunker coal. Coking coal is very strong. Coke is scarce. Home con- sumers complain of inconvenience experienced in conse- quence of the shortage. Little or no coke is obtainable for neutrals. For home use, foundry quality is 38s.; medium blastfurnace kind, 33s. at the ovens ; and low phosphorus sort, 35s. 6d. at the ovens ; whilst for shipment to neutrals, 55s. is named for both foundry and furnace coke. IRON. Distributon of pig iron is heavy, and a fairly large new business is passing. Deliveries of Cleveland foundry iron to Scotland during the current month have been on such a satisfactory scale that quite a number of supplementary allocations have been issued for customers north of the Tweed. All the northern foundries are very busy, but with the holiday period approaching, demand for foundry iron will be smaller. Next week work at the Tyneside foundries will be suspended, and next month the Scottish foundries take a week’s holiday. Production of forge iron is larger, and as consumers have been able to accumulate stocks, there is now no great pressure for delivery of this quality. Export trade shows expansion, though business with Italy is somewhat retarded by difficulty in connection with rate of exchange. For home consumption, No. 3 Cleveland pig, No. 4 foundry, and No. 4 forge are all quoted 95s.; and No. 1 is 99s.; and for shipment to France and Italy No. 3 and the lower qualities are 114s.; and No. 1 is 119s. Better railway facilities have improved home delivery of haematite iron, and shipments to the Allies are larger. Mixed numbers of east coast haematite are 122s. 6d. for home use, and 147s. 6d. for export to France and Italy. Demand for finished iron and steel is heavy. Manufacturers of ship- building material have that class of work well in hand. Prices all round are very stiff. ________ _______ Cumberland. Mary port. COAL. There is no new feature to report in the condition of the coal industry in West Cumberland. The only change noticeable since last week is that the shortage is more pronounced, both for shipping and home use, and even the landsale depots can scarcely get enough to satisfy their customers. In other respects, matters are practically the same as they have been for some weeks. Production is low. The needs of the iron ore mines have probably not been so large of late, but local works requirements are now bigger than ever. The shortage of labour is becoming more acute, in consequence of the comb-out, and unless there is some improvement shortly, it is feared that a shift will have to be dropped at one or two of the pits. Landsale is featureless, and business at the depots is dull, but merchants can easily dispose of all the coal they can