The local authority shall cause a register to be kept, in which shall be entered the names and residences of the keepers of all common lodging-houses within the district of the local authority, and the situation of every such house, and the number of lodgers authorised according to this Act to be kept therein, and in each apartment thereof ; provided that the keeper of every common lodging-house shall apply to the local authority at or previous to the fifteenth day of May in every year for a renewal of such registration; and the local authority may refuse to register any house which they do not consider suitable for the purposes of a common lodging-house, and as the keeper of a common lodging-house any person who does not produce to the local authority a certificate of character in such form as the local authority shall -direct, but notwithstanding such certificate the local authority may, if they see fit, make further inquiry, and may thereafter refuse to register, if they are satisfied that the person applying is not qualified to be the keeper of a common lodging-house; and the local -authority may from time to time, with the approval of the Board, raise or diminish the sum payable per night, according to which, as in this Act mentioned, it is ascertained whether a house or part thereof is a common lodging-house, but so as not to exceed sixpence per night.