MINING 379 



April 8, 1908, before the Institution of Naval Architects), think this the main if not the 

 sole function of the cap; others, such as Chladek and Bahn, attribute considerable im- 

 portance to its (supposed) action in breaking up or otherwise weakening the hard surface 

 layers of the plate before the undamaged point impinges upon them. Those, now-a- 

 days in the majority, who hold the view of Tresidder, naturally use all the weight avail- 

 able in giving lateral support to the cap and put little or no metal in front of the point. 

 Those, on the other hand, who believe that the cap can weaken the plate before the 

 actual impact of the projectile itself, will place some of the metal of the cap in front of the 

 point. From the point of view of external ballistics it is desirable that the external 

 contour of the projectile should be continued to the point, and this is against the flat 

 ended cap suggested by Tresidder. This difficulty can however be met by using a hol- 

 low cap with the bulk of the metal giving lateral support to the point and practically 

 flush with it, but with what may be termed a false head to give it a suitable ogival out- 

 line, as for example in the Firth cap shown on page 291 of Brassey's Naval Annual 

 (1912). (W. E. EDWARDS.) 



MINING 1 



. So far as mining processes and operations are concerned, the principal new develop- 

 ments in the last few years have been connected with coal mining, 2 and reference is 

 chiefly made in the following sections to that industry. 



LEGISLATION. The passage of the Coal-Mines Act, 1911, which came into force, as 

 regards the bulk of its provisions, on July i, 1912, has been the event of outstanding 

 recent importance in the British coal-mining industry. It introduces radical changes in 

 the control and management of coal-mines, and has entailed considerable alterations in 

 the mechanical equipment and methods of working collieries. In France, new coal- 

 mines regulations became operative on February 25, 1912. New Belgian regulations 

 were issued in December 1910 in regard to travelling roads and shafts. Anew Coal- 

 Mines Regulation Act was passed in British Columbia during 1911, and a movement 

 was on foot in 1912 to consolidate the various Provincial Acts in Canada relating to 

 coal-mining. The United States Bureau of Mines was established by Act of Congress 

 on July i, 1910, its purpose being to investigate methods of mining. The headquar- 

 ters of the Bureau are at Washington, and the mining experiment station is situated 

 at Pittsburg with an experimental mine at Bruceton, Pa., and six mine-safety stations 

 and seven mine-rescue cars distributed one in each of the principal coalfields. 



COAL SUPPLY. The three years 1910-1 2 have been notable for the deepening interest 

 that has been shown in regard to the question 6f coal resources. During 1912 the Royal 

 Commission on Conservation appointed by the Canadian Government issued volumi- 

 nous reports (see also An Investigation of the Coals of Canada, Ottawa, 1912, in 6 vols.), 

 and similar enquiries have been prosecuted in the United States, under the auspices of 

 the Geological Survey and the Bureau of Mines. 



In British Columbia, at the headwaters of the Skeena river in what is termed the 

 Groundhog Mountain area, enormous deposits of anthracitic coal have been located, a 

 conservative estimate placing the resources of the coalfield at 3,072,000,000 tons; other 

 smaller basins have also been prospected. The development of the Rocky Mountain 

 Coalfields in British Columbia, Alberta and Manitoba has proceeded apace. D. B. 

 Dowling has estimated that the known areas in Canada underlain by workable coal beds 

 (excluding the Skeena district) cover little short of 30,000 sq. m. and contain a total of 

 172,057,000,000 tons, sub-divided as follows: Nova Scotia, 6,250,000,000 tons; New 

 Brunswick, 155,000,000 tons; Manitoba, 330,000,000 tons; Saskatchewan, 20,000,000,- 

 ooo tons; Alberta, 104,932,000,000 tons; British Columbia, 38,976,000,000 tons; Yukon, 

 914,000,000 tons; Mackenzie District, 500,000,000 tons. Further prospecting has taken 

 place in Alaska, but transport difficulties have still to be overcome, and the same coh- 

 sideration delays the utilisation of the deposits in Siberia and China, in which the 

 existence of enormous quantities of high-class coal is established. In Victoria, Australia, 

 See E. B. xviii, 528 et seq., and allied articles. 2 See E. B. vi, 579 et seq. 



