18.—Unless a different intention appears, the following are rules for ascertaining the intention of the parties as to the time at which the property in the goods is to pass to the buyer.

Rule 1.—Where there is an unconditional contract for the sale of specific goods, in a deliverable state, the property in the goods passes to the buyer when the contract is made, and it is immaterial whether the time of payment or the time of delivery, or both, be postponed.

Rule 2.—Where there is a contract for the sale of specific goods and the seller is bound to do something to the goods, for the purpose of putting them into a deliverable state, the property does not pass until such thing be done, and the buyer has notice thereof.

Rule 3.—Where there is a contract for the sale of specific goods in a deliverable state, but the seller is bound to weigh, measure, test, or do some other act or thing with reference to the goods for the purpose of ascertaining the price, the property does not pass until such act or thing be done, and the buyer has notice thereof.

Rule 4.—When goods are delivered to the buyer on approval or “on sale or return” or other similar terms the property therein passes to the buyer:—

(a) When he signifies his approval or acceptance to the seller or does any other act adopting the transaction:

(b) If he does not signify his approval or acceptance to the seller but retains the goods without giving notice of rejection, then, if a time has been fixed for the return of the goods, on the expiration of such time, and, if no time has been fixed, on the expiration of a reasonable time. What is a reasonable time is a question of fact.

Rule 5.—(1) Where there is a contract for the sale of unascertained or future goods by description, and goods of that description and in a deliverable state are unconditionally appropriated to the contract, either by the seller with the assent of the buyer, or by the buyer with the assent of the seller, the property in the goods thereupon passes to the buyer. Such assent may be express or implied, and may be given either before or after the appropriation is made:

(2) Where, in pursuance of the contract, the seller delivers the goods to the buyer or to a carrier or other bailee or custodier (whether named by the buyer or not) for the purpose of transmission to the buyer, and does not reserve the right of disposal, he is deemed to have unconditionally appropriated the goods to the contract.