BAROMETRIC PRESSURE.

Western Star, 12 January 1915, Page 4

BAROMETRIC PRESSURE.

MINE EXPLOSIONS. Just what relations, if any, exist be. 'tween barometric conditions and explosions in coal mines are still unknown, 'though the matter has been the subject of much discussion and investigation. In f England certain newspapers and other unofficial agencies have for many years issued “colliery warnings” generally based on the assumption that a rapid fall in barometric pressure liberates explosive gas from fissures and cavities in the inines, and thus increases the danger of an explosion. Other ways in which the pressure of the atmosphere may be connected with explosions have however, been suggested. Thus it is possible that high pressure may be more effective than low pressure by causing slight dislocation of the strata. Again, exceptional dryness of the atmosphere, such as is especially associated with anticyclonio weather, may increase the likelihood of dust explosions. The present attitude of the United States Bureau of Mines on this subject is jrt forth in recent correspondence with the

weather bureau. The former bureau does not believe that any particular relation can he established between explosions of fire-damp and low barometric conditions. The accumulation of fire-damp in old work mgs almost always issues at a pressure far higher than atmosphere—even at several times atmospheric pressure—so that

rile ordinary fluctuations of the barometer could have no influence on its issuance. In view of the obscurity in which this subject is enshrouded, the Royal Commission on Explosions in Mines deprecated the is. sue of colliery warnings by the British meteorological office.