2. In sales it is the delivery of possession by the proprietor with an intention to transfer the property to the receiver. Two things are therefore requisite in order to transmit property in this way: 1. The intention or consent of the former owner to transfer it; and, 2. The actual delivery in pursuance of that intention.
3. Tradition is either real or symbolical. The first is where the ipsa corpora of movables are put into the hands of the receiver. Symbolical tradition is used where the thing is incapable of real delivery, as, in immovable subjects, such as lands and houses; or such as consist in jure (things incorporeal) as things of fishing and the like. The property of certain movables, though they are capable of real delivery, may be transferred by symbol. Thus, if the subject be under look and key, the delivery of the key is considered as a legal tradition of all that is contained in the repository. Cujas, Observations, liv. 11, ch. 10; Inst. lib. 2, t. 1, §40; Dig. lib. 41, t. 1, 1. 9; Ersk. Princ. Laws of Scotl. bk. 2, t. 1, s. 10, 11; Civil Code Lo. art. 2452, et seq.