In French law. Contracts are of the following varieties: (1) Bilateral, or syndllagmatiquc, where each party is bound to the other to do what is just nnd proper; or (2) unilateral, where tlie one side only is bound; or (3) commutatif, where one does to the other something which is sup-posed to be an equivalent for what the other does to him; or (4) aldatoire, where the consideration for the act of the one is a mere chance; or (5) contrat de bienfoisancc, where the one party procures to the other a purely gratuitous benefit; or (6) contrat d titre onereux, tthere each party ls hound under some duty to the other. Brown