639.6  On contract — amount due.
  If the plaintiff’s demand is founded on contract, the petition must state that something is due, and, as nearly as practicable, the amount, which must be more than five dollars in order to authorize an attachment.
[C51, §1849; R60, §3175; C73, §2953; C97, §3880; C24, 27, 31, 35, 39, §12083; C46, 50, 54, 58, 62, 66, 71, 73, 75, 77, 79, 81, §639.6]