If any person summoned and returned upon any jury under this or the special Act, . . . F1 do not appear, or if appearing he refuse to make oath, or in any other manner unlawfully neglect his duty, he shall, unless he show reasonable excuse to the satisfaction of the sheriff, forfeit a sum not exceeding ten pounds; and every such penalty shall be applied in satisfaction of the costs of the inquiry, so far as the same will extend; and, in addition to the penalty hereby imposed, every such juryman shall be subject to the same regulations, pains, and penalties as if such jury had been returned for the trial of a civil cause in the Court of Session.