88 THE COLLIERY GUARDIAN. July 10, 1914. reactions again appear to predominate. With different kinds of coal, so far as they have been examined, the same stages are in evidence, but are modified by the kind of coal under examination. It has not yet been found possible to determine the nature of the chemical reactions to which these phenomena are due, but it is significant that the thermal stage between 750 degs. Cent, and 800 degs. Cent, agrees with the critical point estab- lished by chemical methods by Messrs. Burgess and Wheeler, and the authors believe that the remarkable heat evolution noticed above 610 degs. Cent, may be connected with a sequence of reactions which give rise to the production of methane, while the interruption at about 750 degs. Cent, may possibly be ascribed to the formation of large quantities of hydrogen. It is clear that the critical points discovered by the authors may possibly be found to possess practical significance as indicating temperatures at which it would be more profitable to carry out fractional distillations, and we are glad to see that the authors propose to extend their observations by examining the heating curves of those portions of the coal substance which are respectively soluble and insoluble in pyridine. Another interesting investigation by the same authors deals with the influence of red-hot coke upon the gaseous bodies produced by carbonisation. It is generally held that the volatile products of coal distillation may break down more or less as a result of contact with heated surfaces either of coke or the walls of the retort, but very little is definitely known of the nature of the process or of the extent to which it takes place. In the experiments of Burgess and Wheeler on the distillation of coal, these secondary reactions were purposely avoided by removing the gases as quickly as possible. The. authors found that one result of passing the products of distillation over red-hot coke was to increase the total yield of gas by as much as 1,250 cubic feet per ton. One of the causes of this increase was the formation of additional hydrogen owing, as the authors think, to the decomposition of the higher hydrocarbon vapours. At the comparatively low temperature of 800 degs. Cent., at which this experiment was performed, the yield of methane was not affected. Methane, how- ever, was decomposed rapidly at 1,100 degs. Cent, into hydrogen and carbon, thus confirming the earlier conclusions of Drs. Bone and Coward. There was also a considerable decrease in the yield of ammonia. The authors have not concluded these investigations, which are clearly of the highest importance in coke oven practice with respect to by-product recovery. At the seventh Congres de la Propriety Nationalisa- PLiniere^ held at Caen recently, some tion in interesting discussions took place on Holland. the general attitude of the State towards mineral proprietors. Several speakers strongly protested that the refusal to con- sider demands for concessions was illegal and contrary to public interest and the participation of the State in the business of mining merited similar condemnation. These protests have probably been evoked by ‘the deliberate policy of the French Government with respect to demands, but we are especially attracted by the remarks made by M. Van Groenendael on the subject of the Dutch State mining enterprise. The Netherlands Government was one of the last to embark upon a policy of nationalisation shortly after the discovery of valuable coal deposits in the Limburg province a few years ago. The experience has been too short to afford any definite indication of its success or otherwise. M. Van Groenendael now states that the State proposes to sell its Domaniale mine to the company that has thus far been working it under lease from the Government. The interesting point in connec- tion with this transaction is that the purchase money, if the sale takes place, will be mostly German, and one of the ostensible reasons advanced for State ownership at the time the step was taken was the necessity of reserving the coalmines of the country for the nation and of preventing the ingress of foreign capital. The Government, it is interesting to note, now give as their reason for this volte face that “ the proprietor of mines runs too many risks,” and that it is better to “ touch ” 2| millions of florins rather than depend upon the problematical profits that may come from working. M. Van Groenendael declares that the old enthusiasm has vanished. And so another nationalistic bubble is pricked! The Dutch enterprise is the only example of State- ownership of collieries, apart from that in Prussia, to be found in Europe, and the following historical details may, therefore, be of interest. For some time after the discovery of the Campine coalfield, the Belgian Government dallied with nationalisation, but in the end wiser counsels prevailed. In Holland, however, where valuable deposits were discovered about the same time, the Government decided to take an important share in the coal trade. All the necessary facts are given in a valuable memoir by Prof. Clement, of Delft University.* The working of coal in Holland is no new thing, for a mine was at work near Kerkrade, in the Limburg province, so long ago as the twelfth century. In 1795 the State purchased the Domaniale mine from the monks of Bolduc, and worked it until 1845, when a lease of 99 years was granted to the Aix-Maestricht Bailway Company. For some years after the discovery of the new Lim- burg area in 1893, the enterprise remained largely in the hands of German and Belgian interests, but in 1901 the Law was passed reserving to the State nearly the whole of the known area, the existing companies being forbidden to engage in fresh enterprise. Since that date three State mines have been successively opened, one only of which is being worked, whilst further areas have been added to the State domain (Eendracht in 1911 and Champs de la Meuse in 1912). At the same time (in 1904) a State Department was organised termed the “ Bijkoop- sporing van Delfstoffen,” to conduct investigations relating to mines, and this Department has been responsible for the discovery of the Peel and Guelder deposits. In the South Limburg 6,500 hectares remain in the ownership of private firms, and 26,000 hectares belong to the State, and of these 17,000 hectares are workable. The motives that inspired the Netherlands Government can be appreciated. In the first place, there was a genuine desire to prevent the coal resources of the country from passing into the hands of foreigners; secondly, the difficulty of deciding upon the merits of the host of applications for concessions. Over and above these, no doubt, was the opinion that the State could operate the mines to pecuniary advantage. Before the areas could be obtained, an indemnity of 444,000 florins had to be paid in respect of prospecting work, and to this must be added 300,000 florins given to concessionaires in the Eendracht coalfield and 1,848,000 florins in respect of the Meuse coalfield. It is notable that so strong was the opposition to the Government project that, in the case of the Peel coalfield, the Ministry consented to lease instead of working the coal themselves. The State collieries in Holland have not been working sufficiently long to form any judgment of the financial results. Up to the end of 1912 the Government Department already referred to had spent 1,900,000 fr. In that year 315,709 tons were produced at the Wilhelmina Colliery and 9,131 tons at the Emma Colliery, the total output for the country being 1,725,394 tons. As the latter colliery, like the Hendrik Colliery, is still in process of development, attention may be concentrated on the Wilhelmina pit. The returns are as follow :— Florins per ton. Net cost of production ........... 5’38 Price obtained* .................. 7’33 Depreciation, &c.................. 0’96 Net profit ....................... 0’99 * Including the profit from the sales of shale and electric current. The working costs include (per ton) : — General charges, 0’55 fl. ; social charges, 0’40 fl. ; labour, 2’94 fl. ; stores, &c., 0*92 fl. ; motive power, &c., * Annates des Mines, Eleventh Series, vol. iii., 1913, 5, p. 335. 0’57 fl. The production per shift was 830 kilogs. per workman, or 2,270 kilogs. per workman at the face ; and the average daily wage was 2’77 fl. below and 1*95 fl. above ground. The profit and loss account is as follows:— Florins. Depreciation, &C...327,298’73 Reserve for debts 8,000 Profit ..........300,000 Florins. Profits on working..614,803’62 „ on houses... 11,573’48 Various receipts ... 8,921’63 635,298’73 635,298’73 Taking the three mines, the total expenditure up to December 31, 1912, was 13,150,277 47 fl., which had been reduced at that date to 12,191,757’05 fl. Of these, 3,374,438 fl. were in respect of general works, 3,181,812’81 fl. in respect of the Wilhelmina mine, 4,308,703’63 fl. in respect of the Emma mine, and 1,326,802’61 fl. in respect of the Hendrik mine. EXPLOSIVES IN COAL MINES. New Order. The Explosives in Coal Mines Order of June 22, 1914, amends the Order of September 1, 1913, by the addition of certain new explosives to the First Schedule. Further, paragraph (6) of the Fifth Schedule to the Explosives in Coal Mines Order of September 1, 1913, has been amended to read as follows :—“ The Brock Squib, con- sisting of a tapering tube of non-smouldering paper, the larger end of this tube being filled with slow burning fuse composition and coloured yellow to denote the end to be ignited; the smaller end being fitted with a length of quickmatch reaching to the fuse composition and secured in position by crimping the paper case.” Whilst the words “chloride of potassium ” have been sub- stitued for the words “ chlorate of potassium ” in the list of ingredients in the definition of Ammonite No. 4, in the Schedule to the Order dated May 13, 1914. The composition of the new explosives is as follows :— Herculite : Parts by weight. Ingredients. Not more than Not less than Nitro-glycerine 34 32 Nitro-cotton 1’5 ... 0’5 Perchlorate of potassium 28 26 Wood-meal (dried at 100° C.)... 10 8 Oxalate of ammonium 30 28 Moisture 2 — The explosive is to be used only when contained in a non-waterproofed wrapper of parchment paper, with a detonator, or electric detonator, of not less strength than that known as No. 6; the greatest weight of the explosive which may be used in any one shot-hole shall not exceed 16 ozs.; the explosive must have been made at the works of the British Ex- plosives Syndicate Limited, at Pitsea, in the county of Essex. Four ozs. of Herculite gave a swing of 2’72 in. to the ballistic pendulum, compared with a swing of 3’27 in. given by 4 ozs. of Gelignite containing 60 per cent, of nitro-glycerine. Nationalite No. 1: Parts by weight. Ingredients. Not more than Not less than Nitrate of ammonium ... ... 68 ... 64 Trinitro-tuluol .................. 16 ... 14 Chloride of sodium .............. 20*5 ... 18’5 Moisture........................... 1 ... — The explosive shall be used only when contained in a case of stout paper, thoroughly waterproofed with carnauba wax; detonator, No. 7; limit charge, 12 ozs.; makers, the National Explosives Company Limited, at Upton To wans, Gwithian, in the county of Cornwall; ballistic swing of 2’92 in. Neonal No. 1 : Parts by weight. Ingredients. Not more than Not less than Nitro-glycerine 41 39 Nitro-cotton 2’5 ... 1’5 Perchlorate of potassium 15 13 Wood-meal (dried at 100° C.)... 5’5 3’5 Oxalate of ammonium 41 38 Moisture 1 — The explosive shall be used only w’hen contained in a non-waterproofed wrapper of parchment paper; deto- nator, No. 6; limit charge, 30 ozs.; makers, the New Explosives Company Limited, at Stowmarket, in the county of Suffolk; ballistic swing of 2’51 in. Stomonal No. 1 : Parts by weight. Ingredients. Not more than Not less than Nitro-glycerine 11 9 Nitrate of ammonium ... 57’5 ... 54’5 Nitrate of sodium 7 5 Chloride of sodium 20’5 ... 18’5 Wheat flour (dried at 100° C.) 8’5 ... 6’5 Moisture 2 — The explosive shall be used only when contained in a stout case of paper thoroughly waterproofed with ceresine, carnauba and paraffin waxes; detonator, No. 6; limit charge, 20 ozs.; makers, the New Explosives Com- pany Limited, at Stowmarket, in the county of Suffolk; ballistic swing of 2’68 in. Super-Excellite No. 3 : Parts by weight. Ingredients. Not more than Not less than Nitro-glycerine 10’5 ... 8'5 Nitro-cotton 1 0’25 Nitrate of ammonium 61 57 Chloride of sodium 16 14 Oxalate of ammonium 11’5 ... 9’5 Starch (dried at 100° C.) 5 3 Castor oil 1’5 ... 0’5 Moisture 2 — The explosive shall be used only when contained in a case of paper thoroughly waterproofed with paraffin wax; detonator, No. 6; limit charge, 36ozs. (This was