Coal mines. A bill to remove for a period not exceeding one year the limitation upon the number of days on which the hours of employment below ground in coal mines may be extended under section three of the Coal Mines Regulation Act, 1908, to restrict the duration of such extensions to half an hour on any one day, and to provide for the maintenance during the period aforesaid of minimum percentage additions to basis rates of wages and of subsistence rates of wages [electronic resource].