Special terms may be held whenever the court shall so direct, but three weeks’ published notice of the order appointing the same shall be given at the seat of government. Any term may be continued from time to time by orders announced in court and entered in the minutes. Any three justices may hold the court and exercise its powers. Unless three shall attend at the time for opening court, those present, or, if all be absent, the clerk, shall adjourn the court until the following day; but, if three justices be absent for six consecutive days, the court shall stand adjourned without day.