''In this Act, unless there is anything repugnant in the subject or context,— (a) “agent”, when used in relation to a mine, means any person appointed or acting as the representative of the owner in respect of the management of the mine or of any part thereof, and as such superior to a manager under this Act ; (b) “Chief Inspector” means the Chief Inspector of Mines appointed under this Act ; (c) “child” means a person who has not completed his fifteenth year ; (cc) “ day ” means a period of twenty-four hours beginning at midnight : (d) a person is said to be “employed” in a mine who works under appointment by or with the knowledge of the manager, whether for wages or not, in any mining operation, or in cleaning or oiling any part of any machinery used in or about the mine, or in any other kind of work whatsoever incidental to, or connected with, mining operations...''