18. Where there is a contract for the sale of unascertained goods, no property in the goods is transferred to the buyer unless and until goods are ascertained.

19. (1) Where there is a contract for the sale of specific or ascertained goods the property in them is transferred to the buyer at such time as the parties to the contract intend it to be transferred.(2) For the purpose of ascertaining the intention of the parties regard shall be had to the terms of the contract, the conduct of the parties and the circumstances of the case.(3) Unless a different intention appears, the rules contained in section 20 to 24 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.

20. 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 to the price or the time of delivery of the goods, or both, is postponed.

21. 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 is done and the buyer has notice thereof.

22. 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 is done and the buyer has notice thereof.

23.(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 (whether named by the buyer or not, for the purpose of transmission to the buyer, and does not reserve the right of deposal, he is deemed to have unconditionally appropriated the goods to the contract.

24. 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.

25.(1) Where there is a contract for the sale of specific goods or where goods are subsequently appropriated to the contract, the seller may, by the terms of the contract or appropriation, reserve the right of disposal of the goods until certain conditions are fulfilled. In such case, notwithstanding the delivery of the goods to a buyer, or to a carrier or other bailee for the purpose of transmission to the buyer, the property in the goods does not pass to the buyer until the conditions imposed by the seller are fulfilled.(2) Where goods are shipped or are dispatched by railway and are by the bill of lading or by railway receipt deliverable to the order of the seller or his agent the seller is prima facie deemed to reserve the right of disposal.(3) Where the seller of goods draws on the buyer for the price and transmits the bill of exchange and bill of lading or railway receipt to the buyer together, to secure acceptance or payment of the bill of exchange, the buyer is bound to return the bill of lading or railway receipt if he does not honour the bill of exchange and if he wrongfully retains the bill of lading or railway receipt the property in the goods does not pass to him.

26. Unless otherwise agreed, the goods remain at the seller's risk until the property therein is transferred to the buyer, but when the property therein is transferred to the buyer, the goods are at the buyer's risk whether delivery has been made or not:Provided that, where delivery has been delayed through the fault of either buyer or seller, the goods are at the risk of the party in fault as regards any loss which might not have occurred but for such fault:Provided also that nothing in this section shall affect the duties or liabilities of either seller or buyer as a bailee of the goods of the other party.

27. Subject to the provisions of this Act and of any other law for the time being in force, where goods are sold by a person who is not the owner thereof and who does not sell them under the authority or with the consent of the owner, the buyer acquires no better title of the goods than the seller had, unless the owner of the goods is by his conduct precluded from denying the seller's authority to sell:Provided that where the mercantile agent is, with the consent of the owner, in possession of the goods or of a document of title to the goods, any sale made by him, when acting in the ordinary course of business of a mercantile agent, shall be as valid as if he were expressly authorized by the owner of the goods to make the same; provided that the buyer acts in good faith and has not at the time of the contract of sale notice that the seller has not authority to sell.

28. If one of several joint owners of goods has the sole possession of them by permission of the co-owners, the property in the goods is transferred to any person who buys them of such joint owner in good faith and has not at the time of the contract of sale notice that the seller has not authority to sell.

29. When the seller of goods has obtained possession thereof under a contract voidable under section 19 or section 19A of the Contract Act, 1872, but the contract has not been rescinded at the time of the sale, the buyer acquires a good title to the goods, provided he buys them in good faith and without notice of the seller's defect of title.

30. (1)Where a person, having sold goods, continues or is in possession of the goods or of the documents of title to the goods, the delivery or transfer by that person or by a mercantile agent acting for him, of the goods or documents of title under any sale, pledge or other disposition thereof to any person receiving the same in good faith and without notice of the previous sale shall have the same effect as if the person making the delivery or transfer were expressly authorized by the owner of the goods to make the same.