A court of summary jurisdiction, in order to allow time for inquiry into any case, or for any other necessary cause, and without calling on the accused to plead to any charge against him, may from time to time continue the case for such reasonable time as may in the circumstances be necessary, not exceeding in all a period of seven days, or on special cause shown 21 days, from the date of the apprehension of the accused, and may liberate him on bail or commit him to prison, either without bail or with bail to an amount fixed by the court:

Provided that no judge shall be entitled to allow bail in a case which he is not competent to try.