According to the Twelve Tables, the powers of a testator in disposing of his property were unlimited; but in process of time, laws were enacted to restrain immoderate or unnatural bequests. By the Falcidian law, in the time of Augustus, no one could leave in legacies more than three fourths of his estate, so that the heirs could inherit at least one fourth. Again, a law was passed by which the descendants were entitled to one third of the succession, and to one half if there were more than four. In France, if a man die leaving one lawful child, he can dispose of only half his estate by will; if he leaves two children, he can dispose only of one third; if he leaves three or more children, then he can dispose by will of only one fourth of his estate. In England, a man can disinherit both his wife and children. These, and many other matters,--bequests in trust, succession of men dying intestate, heirs at law, etc.,--were regulated by the Romans in ways on which our modern legislators have improved little or none. In the matter of contracts the Roman law was especially comprehensive, and the laws of France and Scotland are substantially based upon the Roman system. The Institutes of Gaius and Justinian distinguish four sorts of obligations,--_aut re, aut verbis, aut literis, aut consensu_. Gibbon, in his learned chapter, prefers to consider the specific obligations of men to each other under promises, benefits, and injuries. Lord Mackenzie treats the subject in the order of the Institutes:-- "Obligations contracted _re_--by the intervention of _things_--are called by the moderns real contracts, because they are not perfected till something has passed from one party to another. Of this description are the contracts of loan, deposit, and pledge,--security for indebtedness. Till the subject is actually lent, deposited, or pledged, it does not form the special contract of loan, deposit, or pledge." Next to the perfection of contracts by _re_,--the intervention of things,--were obligations contracted by _verbis_, spoken _words_, and by _literis_, or writings. The _verborum obligatio_ was contracted by uttering certain words of formal style,--an interrogation being put by one party, and an answer given by the other. These stipulations were binding. In England all guarantees must be in writing. The _obligatio literis_ was a written acknowledgment of debt, chiefly employed when money was borrowed; but the creditor could not sue upon a note within two years from its date, without being called upon also to prove that the money was in fact paid to the debtor. Contracts perfected by consent, _consensu_, had reference to sale, hiring; partnership, and mandate, or orders to be carried out by agents. All contracts of sale were good without writing.