There shall be one General Land Office in the State, which shall be at the Seat of Government, where all Land Titles which have emanated or may hereafter emanate from the State shall be registered, except those titles the registration of which may be prohibited by this Constitution. It shall be the duty of the Legislature at the earliest practicable time to make the Land Office self sustaining, and from time to time the Legislature may establish such subordinate Offices as may be deemed necessary.