At the hearing of such application the Court or judge shall inquire fully into the estate of the deceased person, and for that purpose may –

(a) summon and examine the persons who are entitled to make an application under this Act, or such of them as the Court or judge may think it desirable to examine, and also such witnesses as may be necessary; and

(b) require the executor or person applying for probate or letters of administration to furnish full particulars of the estate.