Ad Dig. 3,5,30Windscheid: Lehrbuch des Pandektenrechts, 7. Aufl. 1891, Bd. II, § 482, Note 8.Papinianus, Opinions, Book II. A certain man directed a freedman or a friend to borrow money, and the creditor, on the faith of the letter, made the agreement, and the surety was given. In this instance, although the money was not expended upon property, still an action is granted to the creditor or his surety, against the party, on the ground of business transacted; which certainly bears a resemblance to the Actio Institoria. 1A man who was transacting business for Sempronius, ignorantly attended to a matter in which Titius was interested. He will be liable to Sempronius also, on account of this particular matter, but he can make an application to the court for a bond of indemnity against Titius, to whom a right of action is granted. The same rule applies to the case of a guardian. 2Where a case was ready to be heard, and the defendant did not appear, a friend of his voluntarily took his place, and stated the cause of his absence to the court. The latter will not be considered to have been guilty of negligence, if he did not appeal where a judgment was rendered against the party who was absent. Ulpianus says in a note, that this is correct, because the first party in default lost his suit; but where a friend defends an absent person and permits judgment to be taken against him, and brings suit on the ground of business transacted, he will be rendered liable, if he does not appeal when he could do so. 3A person who transacts the business of another is obliged to pay interest on any money in his possession, after the necessary expenses have been settled. 4A testator stated that his freedman should be paid a certain sum of money for the expense of erecting a monument; and if anything beyond that amount was expended, suit cannot be brought for it on the ground of business transacted, or on that of a trust, since the wish of the testator established a limit to the expenditure. 5The heir of a guardian, who is a boy under the age of puberty, is not liable for matters attended to by his guardian with reference to the property of the female ward of his father; but the guardian of the boy may be sued in his own name on the ground of business transacted. 6Although a mother may transact the business of her son in accordance with the will of his father, through the inducement of natural affection; still, she will not have authority to appoint an agent, at her own risk, for the purpose of instituting legal proceedings, because she cannot herself legally act in behalf of her son, or alienate her property, or discharge a debtor of the minor by accepting payment. 7Where one party defended a case in which a common right of water was involved, and judgment was rendered in favor of the owner of the land; he who paid the necessary, reasonable expenses in the case where both were interested, will be entitled to an action on the ground of business transacted.