1326 THE COLLIERY GUARDIAN December 11, 1914 inventor can at least claim that he has reduced to a commercial proposition the production of an oil lamp that is all that can be desired from the stand- point of illumination. Illumination, however, is only one of several properties to be striven for in the perfection of the safety lamp, and that this desirable stage has not yet been reached in either type of lamp will be readily admitted by all except those who have private axes to grind. When the electric and oil lamps come up for judgment, there can be no real criterion except that of actual practice. To quote a recent paper issued by the United States Bureau of Mines, “ The user of a device is the logical one to specify its qualities. If the user is obliged to adapt his actions, operations, or equipment to the limitations of the manufacturer, the product of such a manufacturer is not practicable in the fullest sense of the word.” Briefly, we should characterise the desirable qualities of a safety lamp as being the following : — (1) Safety; (2) lighting capacity ; (3) portability; (4) first cost; (5) cost of maintenance. Now scarcely one of these factors is a simple question of fact, and for that reason there is little to be gained from the arguments employed to foster the sales of particular lamps or types of lamps. Taking first the question of safety, the only one that the Bureau of Mines has so far endeavoured to test, there seems to be evidence that, except under the most abnormal conditions, a well-constructed electric lamp is safe. But safety can only be relative and never absolute, and the oil lamp, through its capacity to detect the presence of inflammable or noxious gases, holds for the present a distinct advan- tage over its rival; for it cannot be positively asserted that the claims of any of the accessories that have been introduced for the purpose of detecting or determining firedamp have yet been definitely estab- lished, and, until that stage has been reached, the oil lamp can never be entirely banished from the fiery mine. On the other hand there are many— and they disinterested users—who look upon the oil lamp as containing several distinct elements of danger under conditions that may be calculated to arise in practice; and it has been pointed out that the British official test does not, in any but an indirect sense, cover this question of safety, whilst, undoubtedly, the oil lamp is an instrument that lends itself to abuse in the hands of reckless or careless workmen. It is unnecessary here to enlarge upon the value of light, which is the chief function of a lamp, but it should be observed that the lighting effect is a more complex affair than is commonly supposed; not only have we to consider the actual intensity of the light, but it is necessary to compare the spread and t( flux ” of light, as well as its colour and quality, its consistency and duration. Having a regard to all these points, the electric lamp seems to hold some advantage under the most favourable conditions, and the improvements in filaments and batteries have greatly increased the portability of the lamp and the permanence of the maximum lighting capacity. It is clear, however, that bad construction and unintelligent supervision may counterbalance the degradation of the flame lamp that is necessarily due to the conditions of use. As regards portability it would seem that the oil lamp can still hold the field, although the electric lamp can accommodate itself to almost any angle and position; and it is the same with the question of first cost. The first cost of an article, however, can only be considered in relation to the work that it performs, and here the first cost is so intimately bound up with the cost of maintenance, that it really has no independent significance. It is around this point, indeed, that the whole controversy seems to centre. The figures that have been obtained from repre- sentative installations are totally at variance, and many managers have produced altogether different results from those put forward by Mr. Hargreaves at the recent meeting of the Midland Institute ; we suspect that it is again the old story that has been told so often where electrical matters are concerned —that is, the fatal policy of placing electrical plant in the charge of inexperienced men. In the past the lampman at a colliery has generally been a steady superannuated miner, who by tradition, if not by experience, has acquired a serviceable knowledge of the safety lamp and its simple requirement^. To place such a man, without training, in charge of an electric lamp installation, with its delicate charging apparatus, is to beg trouble. At the same time, collieries are not run for show, and it is not every pit that can afford to employ a skilled electrician in its lamp station. Up to the present the most successful results from electric lamps have been obtained at large collieries, whose lamp equipment has justified the employment of men of this class. But it seems to us to be useless to quote the cost of upkeep with the omission of the labour cost In conclusion, we think it is unlikely that mining engineers will take sides in this controversy, nor take for granted everything that they are told by makers and agents. Discussions such as those at Sheffield and Manchester are to be welcomed, because they encourage lamp users to scrutinise the experience which they obtain, and to publish the results for the benefit of others. The Midland Institute in the past has rendered valuable services to the industry in this field of research, and it is still fertile. Apart from the independent work of members, the institute might possibly help by giving to the various qualifica- tions of the safety lamp cited above their proper value. Finally, although we have a perfectly open mind on this question, we may express the opinion that some of the oil lamp people are taking a wrong line in attempting to discredit the electric lamp. The lamps now on the market may have defects, but it is certain that these will be removed in time, and an extremely valuable and commodious appliance placed in the hands of the miner. THE IRISH COAL TRADE. Thursday, December 10. Dublin. The coal trade generally maintains a fair amount of activity, although buying is scarcely in such large quantities as is usual at this season, the disposition being mostly to provide for present wants. The tempestuous weather of the past week has not only delayed the arrival of colliers by several days to this port, but a number which sailed from Dublin for cross-Channel ports were compelled to abandon their passages and put back again into the shelter of the Liff’ey, the result being the smallest delivery of coal at the wharves for several months past. There has been a sharp advance in freights, and should present conditions continue, there will undoubtedly be an early advance in prices of coal. At the moment there is no change in any of the qualities, although Scotch coals are already dearer in some districts. Quotations in the city are as follow:—Best Orrell, 27s, per ton; Hulton Arley, 26s.; best Wigan, 25s.; best Whitehaven, 25s.; Pemberton Wigan, 23s.; kitchen nuts, 22s.; Orrell slack, 21s.—all less Is. per ton discount for cash ; house coal, retail, Is. 7d. per sack; steam coals about from 22s. to 23s. per ton; best coke, 22s. per ton. Pit mouth prices of Irish coals at Wolfhill Colliery, Queens County, are ?—Large coal, 21s. 8d. per ton; Is. Id. per cwt.; small coal, 20s. per ton, Is. per cwt.; nut coal, 16s. 8d. per ton; lOd. per cwt.; culm, from Is. 8d. to 10s. per ton. The coaling vessels arriving during the week amounted to 32, as compared with 38 the week previously, chiefly from Glasgow, Point of Aire, Partington, Liverpool, Ellesmere Port, Ayr, Neath Abbey, Gars ton, Newport and West Bank. The total quantity of coal discharged upon the quays was 13,533 tons, as against 15,281 tons in the previous week. Belfast. Demand is still improving both locally and at inland districts, and an advance of 6d. per ton has been made in coals for the trade in connection with the latter. Stocks of some qualities of Scotch coals are considerably diminished owing to the difficulty in obtaining supplies at the other side, and difficult sea passages during the past week have retarded steamers from English ports, in consequence of which stocks are rather low at present, and freights con- siderably advanced. Scotch steam coals and slack are Is. per ton higher, and prices still tend in an upward direction. There is no change in other descriptions. The following are the current quotations :—Best Arley house coal, 27s. 6d. per ton; Scotch house coal, 23s. 6d. per ton; Orrell nuts, 26s. 6d.; Orrell slack, 23s. 6d.; Scotch steam coal, 17s. to 18s. per ton; Scotch steam slack, 12s. 6d. to 13s. 6d.; Welsh steam coal, 17s. to 18s. per ton delivered. Coaling vessels arriving during the week were chiefly from Ayr, Garston, Preston, Glasgow, Ardrossan, Briton Ferry, Ellesmere Port, Workington, Saundersfoot, Whitehaven and West Bank. Between November 15 and 28 the total number of coal-laden vessels entering the harbour was 102. During the first eight months of the present year 6,989,108 tons of coal and coke were imported into Italy, valued at 241,124,226 lire, as compared with 7,094,592 tons, valued at 244,763,424 lire, in the corresponding period of 1913. THE COAL AND IRON TRADES. Thursday, December 10. Scotland.—Western District. COAL. The market in the west of Scotland continues strong, and most classes of coal are in active demand. Shipments during the past week amounted to 80,185 tons, compared with 121,733 in the preceding week and 96,545 tons in the corresponding week of last year. Everything points to the present high level of prices being maintained for a con. siderable time to come, but those connected with the trade are aware how easily the whole complexion may be altered. Prices f.o.b. Glasgow. Steam coal.............. Ell .................... Splint.................. Treble nuts ............ Double do............... Single do............... Current L'st week's prices. prices. 10/9-12/6 1 10/9-12/9 13/3—13/6 13/ -13/3 12/6-14/9 ! 12/ -14/9 11/9-12/ s 11/3-11/6 10/9-11/3 | 10/3-10/6 10/3 10/ -10/3 Last year's prices. 13/ -14/6 13/3-13/9 13/3-16/9 13/ 12/3-12/6 10/9-11/ IRON. The tone in the pig iron trade has improved considerably during the past week. Consumers of ordinary and haematite qualities have not only been disposed to purchase in larger quantities than they have considered justifiable for a long time past, but they are also more inclined to cover their requirements further ahead. Consequently the position of makers has strengthened, and prices are tending upwards— particularly in the case of haematite iron, the consumption of which has expanded more readily than ordinary qualities. The shipping branch of the trade, however, is somewhat restricted owing to the high rates of freight. The number of furnaces in blast in Scotland at present is 68, compared with 72 in the preceding week and 76 in the corresponding week last year. The volume of business transacted in the Glasgow pig iron warrant market during the week was fairly satisfactory, and prices showed a further advance, business being done at 52s. per ton cash. Towards the close, however, the market was not so well supported, but nevertheless the closing quotation of Cleveland iron at 51s. 7d. per ton cash buyers represented a gain of 2|d. per ton on the week. The total turnover amounted to 11,000 tons. Warrant stores have increased by 816 tons, and now amount to 105,310 tons, compared with 147,982 tons in the same period of 1913. The manufacturing branches of the trade show little progress. Some producers are busily engaged, principally on Government work, but generally speaking trade is not so satisfactory as could be desired. Scotland.—Eastern District. COAL. The total shipments from the Lothians district only amounted to 30,320 tons, against 47,549 in the preceding week and 89,593 tons in the same week last year. Business on the whole, however, is fairly good, and the collieries are more favourably placed. Steams are comparatively well booked, and smalls are in good request. Prices f.o.b. Leith. Best screened steam coal... I Secondary qualities..... Treble nuts ............ Double do............... Single do............... Current prices. 11/ -11/3 10/ -10/3 11/9-12/3 10/3-10/6 10/ L'st week's prices. 11/ 10/ 11/3-11/6 10/ -10/3 10/ Last year’s prices. 13/ -13/6 11/9-12/6 13/3-13/9 12/3-12/6 10/9-11/ Conditions in the Fifeshire market are steady, but business prospects do not appear to be of the best. Navigations and first-class steams are better placed, but third-class steams are very quiet, and broken time is very much in evidence. Washed nuts are steady, although in some instances stocks are inclined to accumulate. The clearances for the week amounted to 39,440 tons, compared with 62,319 in the preceding week and 88,037 tons in the corresponding week of last year. Prices f.o.b. Methil or Burntisland. Best screened navigation coal Unscreened do First-class steam coal Third-class do Treble nuts Double do Single do Current prices. 15/6-15/9 13/6 11/6-11/9 10/ 11/ -12/ 10/3-10/9 10/ -10/3 L’st week’s prices. 15/6-15/9 13/6 11/6-11/9 10/ 11/3-11/9 10/ -10/6 10/ Last year's prices. 16/9 14/9 12/6-13/ 10/9-11/ 13/ -13/6 11/9-12/ 10/6 The aggregate clearances from Scottish ports during the past week amounted to 149,945 tons, compared with 231,601 in the preceding week, and 274,175 tons in the corresponding week of last year, showing a decrease of 81,656 tons and 124,230 tons respectively.