Sale, in law, a contract to give and transfer rights of property for money, which the buyer pays or promises to pay to the seller for the thing bought and sold. The word is often applied indifferently to the transfer, for a consideration, of both real and personal property; but in its proper and technical sense it applies only to that of personal property, the transfer of real property passing under the denomination of a grant or conveyance. The difference between a sale and an exchange is that in the former the price is paid in money, while in the latter it is paid in goods. Three things are necessary to constitute a valid sale at common law, viz.: the thing to be sold, the price to be paid for it, and the agreement or consent of the contracting parties that the property in the subject matter should pass from the vendor to the vendee, for the stipulated price given or promised to be given by the vendee. If there is no evidence that the sale is on credit, an agreement for immediate payment is implied; and if the vendee leaves without paying, the vendor may rescind the sale and demand and recover his goods.

But the actual delivery of a chattel, and the acceptance of earnest or part payment by the seller, is evidence of an implied agreement between them that something is left to be done in future, and the legal presumption of immediate payment is thereby rebutted. The buyer however cannot take the goods, notwithstanding earnest be given, without full payment, unless it is an express condition of the sale. If he does not come, in a reasonable time after request, and pay for and take the goods, the contract may be dissolved by the seller, and he is at liberty to sell the goods to another person. But where express terms are agreed upon whereby the delivery or the payment is postponed to a future time, the sale is complete, and the property in the chattel passes immediately to the buyer. The thing sold must be in actual existence at the time of the sale, otherwise the sale will be invalid. If one man sells to another a horse, and the horse is dead, or if he sells a house or other property which has been destroyed by tire, both parties being ignorant of the fact before sale, it is invalid.

If a part only of the subject matter is non-existent or destroyed, and the remainder is capable of transfer or delivery, the buyer has the liberty, at his option, either to rescind or enforce the contract as to such remainder. The price to be paid must be ascertained and certain, or so referred to a definite standard that it may be made certain; and the thing sold must also be specific or capable of a certain identification. When made by letter, the contract is complete as soon as a distinct proposition contained in it is accepted bona fide, by letter written within a reasonable time, and mailed before the acceptor receives information of a withdrawal of the offer. If the thing is sold for cash, the vendor is entitled to hold possession of it until he receives his pay. He cannot sue for the price until the goods are delivered or tendered; but if they are accidentally destroyed while thus in his possession, and without any fault or carelessness on his part, he may then sue for the price. If the price is not paid, whether the goods are sold for cash or on credit, and they remain in the hands of the seller, he has a lien on them for the price.

This lien is destroyed by either actual or constructive delivery of the goods; and if he takes a bill of exchange or promissory note as security for the price, he also loses his lien. After a sale of personal property and a fair and absolute delivery to the purchaser personally, the seller cannot reclaim or retake possession of the property (upon the ground of a lien), because the consideration which was to have been given at the time of the delivery has not been paid, even though the purchaser shortly after becomes insolvent; for the seller's lien being once lost or waived by the delivery, it cannot reattach. - A sale without delivery is not valid, in general, against a third person who buys without notice; and if the goods are sold by the vendor to two different and innocent parties, by transfers equally valid, he who first obtains possession of the goods will hold them. But as between the seller and the purchaser, delivery is not necessary to complete the bargain; though as between the seller and his creditors a strong inference arises, in the absence of delivery, that the sale itself is colorable, and intended as a fraud upon the creditors. This inference is not conclusive, but is one of fact to be considered by the jury in connection with other circumstances.

Symbolical delivery will in many cases be sufficient and equivalent in its legal effect to actual delivery. The delivery of the key of a warehouse in which the goods sold are deposited; or transferring them in the warehouseman's or wharfinger's books to the name of the buyer; or the delivery of a part as representative or as an instalment of the whole, is a delivery sufficient to transfer the property. When the goods sold are of such a nature or in such a situation that a personal possession of them is impracticable or inconvenient, the simple sale and an agreement of the parties will pass the property to the purchaser without actual delivery. If no particular time is appointed by the terms of the contract for delivery or payment, these must be made within a reasonable time; and the seller is bound to keep the things sold until time of delivery with ordinary care and good faith; otherwise he will be liable should they be injured or destroyed. If the contract is to deliver at the residence of the buyer or any other particular place, and this is not done, the seller is liable even though such a delivery becomes impossible, unless it becomes so through the act or fault of the purchaser.

If the goods are to be delivered to the purchaser, but no place of delivery is named, they must be sent to him wherever he may happen to be, or to his house or place of business, unless they were bought to be used for any particular purpose, or at any particular place. When a time and place are expressed in the contract of sale, the buyer must receive and pay for them then and there, and also pay all reasonable charges for keeping after the sale and before delivery. If the goods are sold on credit, and the purchaser should become insolvent before delivery, the seller may demand security and refuse to deliver without. - Whenever, in a contract of sale, it is agreed that some particular act shall be done in relation to the thing sold, by either party, as that the goods shall be delivered on a particular day, or on request, or that a promissory note shall be given, this makes a conditional sale. So it is a condition precedent where some act remains to be done, such as weighing or measuring; and if there is no evidence tending to show the intention of the parties to make an absolute and complete sale, the property does not pass wholly to the buyer until such condition is performed.

If the buyer neglects or refuses to comply with a condition precedent, and the goods are therefore not delivered, the seller may, after due delay and precautions, resell them, and hold the buyer responsible for any deficiency in the price. In all of these cases the property in the thing sold passes to the buyer by the fact of sale, but he holds it subject to the lien or other reserved right of the seller. One class of sales on condition are those known as "contracts of sale or return," where possession of the goods is given to the purchaser with the privilege of keeping them or returning them within a specified time. If he returns them within this time, the contract is rescinded; but otherwise the sale becomes absolute and complete. When goods are sold by auction, the conditions of sale made known to the buyer by the advertisement, or communicated by the auctioneer at the time of sale, bind both parties, and regulate the transfer and possession of the property. When goods which are only a numerical proportion of an entire bulk are sold, no property passes and the sale is incomplete until such part has been separated and set apart from the remainder and actually delivered. - The seller of goods has not only a lien upon them for the price while they remain in his possession, but he may, in the event of the bankruptcy or insolvency of the purchaser, after he has parted with the possession of them, and while they are in transitu on their way to the purchaser, retake them, the price being unpaid. (See Stoppage in, Transitu.) A sale of goods with intent to delay, hinder, or defraud a creditor, though good as between the parties, is utterly void as against the creditor, even if the purchaser pays full value for them, unless the purchaser was ignorant of the fraud and purchased them in good faith, as well as for a good consideration. - Contracts of sale which have an immoral or illegal object in view are void at common law.

Contracts with an enemy for the purchase or sale of goods, and contracts in contravention of statutory provisions, are illustrations of this rule. The obtaining goods upon false pretences, under color of purchasing them, does not change the property; but it has been held that a bona fide purchaser of goods for a valuable consideration, from a person who obtained them from the owner by false pretences, amounting even to a felony, will hold them against the first seller, if he (the first seller) voluntarily parted with the possession and intended to part with the title. The sale will never be valid in favor of the purchaser where he obtains the goods by fraud practised upon the seller under color of a purchase, whether on credit or otherwise. Thus, if an infant fraudulently represents him self to be of full age, and by such false representation succeeds in obtaining goods on credit, the sale will be void, and the seller may reclaim the goods from the buyer, or from any one who has not bought the goods of the buyer for value, and in ignorance of the fraud. If a person steals goods and sells them, the property is not thereby changed, but remains in the rightful owner, who may reclaim them wherever they may be found.

In England there is an exception to this rule, which is where the goods are sold by the wrongful possessor in market overt, in which case the sale is binding upon the true owner, and the purchaser obtains a good title. But in this country no sale of goods by the wrongful possessor is valid. (For sale with warranty, see Warranty.) A conjectural estimate of the value is not a misrepresentation which might avoid the sale; and concealment, to be fraudulent and material, must be a concealment of something which the party was bound to disclose. A seller is unquestionably liable to an action for deceit if he fraudulently represents the quality of the thing sold to be other than it is, in some particulars which the buyer has not equal means with himself of knowing; and he is if he do so in such a manner as to induce the purchaser to abstain from making the inquiries which for his own security and advantage he would otherwise have made.