and is immediately complete; for the seller gets a fixed price of 100 aurei, which will be increased if the purchaser gets more for the lands.

8. POMPONIUS.

There cannot possibly be a purchase or sale without a thing for sale; and yet future produce and young unborn may lawfully be purchased, with the result that, on the occurrence of the birth, the sale is regarded as completed at the time when the bargain was made; but if the seller tries to prevent the subject coming into existence, the action on purchase is competent.

must be paid in any event, whether much, or little, or nothing comes of the chance. The contract is absolute for the buyer, but the obligation of the seller is conditional upon the existence of the thing. Pomponius treats it as an exceptional case of a sale sine re; but that is a misconception, the true subject of the sale being the prospect or chance of getting the thing, and not the thing itself, just as in the sale of a lottery ticket, or of a horse's chance of winning a race, the equivalent for the price is a chance, which is very likely to prove worthless, but in the meantime possesses a money value. Such a chance is a res,' in the wide jural sense of the word, quite as much as a claim of debt or other incorporeal is. For examples of emptio spei,' see also D. 19. 1. 12; ib. 18; 17. 4. 7; ib. 11. The usual example, a cast of a fisherman's net, is rather a case of hire of materials and labour than of sale, at least as regards fish in the sea, which are not the property of the fisherman till he catches them.

It was a question of construction in each case whether the parties intended the one kind of bargain or the other. It is not clear, as is often asserted, that there was a presumption in case of doubt that a conditional sale (emptio rei speratae) was meant.

Missilia means things thrown as largess to the mob: it was held to be the intention of the owner to transfer the property to an uncertain person, and so each individual in the crowd becomes owner of what he gets (Inst. ii. 1. 46; D. 41. 1. 9, 7); the present text implies that the appropriation is not complete till the scramble is over, the seller in the case figured not being

1. Aliquando tamen et sine re uenditio intellegitur, ueluti cum quasi alea emitur. quod fit, cum captum piscium uel auium uel missilium emitur: emptio enim contrahitur etiam si nihil inciderit, quia spei emptio est: et quod missilium nomine eo casu captum est si euictum fuerit, nulla eo nomine ex empto obligatio contrahitur, quia id actum intellegitur.

9. ULPIANUS libro XXVIII ad Sabinum.

In uenditionibus et emptionibus consensum debere intercedere palam est ceterum siue in ipsa emptione dissentient siue in

answerable for what he picks up, and then has wrested from him (evictum), but only for what he gets and can keep.

For the sale of future things in the sense of goods to be made to order, to be manufactured, see Inst. iii. 24. 4; D. 19. 2. 2, 1; h. t. 20 and 65; Windscheid, § 401. 3.

""future

It is mostly in this sense that we now use the term: goods" means goods to be manufactured, or acquired by the seller after the making of the contract of sale,' S. G. B. § 62: they may be the subject of an agreement to sell, but not of an actual sale so as to pass the property and the risk, § 5, cp. §§ 18-20; Lunn v. Thornton (1845) 1 C. B. 379 (goods which should at any time thereafter remain and be in the dwelling-house'). This distinction is quite foreign to the Roman law.

The sale of a spes is recognised by our chief modern authorities -Pothier, § 6; Erskine, 3. 3. 3.; Benj. p. 87; but there seem to be no decided cases quite in point. See, however, dicta per Martin, B., 'No doubt a man may buy a chance of obtaining goods, but here the plaintiff bought the slates' (Buddle v. Green (1857) 27 L. J. Ex. 24); and per Richards, C. B., ‘If a man will make a purchase of a chance, he must abide by the consequences' (Hitchcock v. Giddings, 4 Price 135). The sale of an expected inheritance (which is not illegal by our law, Ragg v. Brown (1708) Mor. 9492; Cook v. Field (1850) 15 Q. B. 460) and of a goodwill (at least in the sense of Lord Eldon's definition, 'the chance that the old customers will resort to the old place') are perhaps the nearest analogies to the emptio spei.

Several illustrations of the emptio rei speratae occur. Thus it was held in the old case of Grantham v. Hawley (quoted by

1. In some instances, however, we can conceive of sale even without a thing sold, as when one buys a chance.' Such is the case when you buy the haul of a fisherman's or fowler's net, or all the largess one can pick up, for there is a valid sale even if nothing should be got, because you bought an expectation; and, as regards the sale of largess, the seller incurs no obligation in respect of anything that is wrested from him after he has caught it, for that is presumed to have been the intention of the parties.

9. ULPIAN.

Consent is of course a necessary element in every contract of sale; and if the parties are not agreed,-whether about the Benj. p. 82.) that there could be a valid sale of future goods which had a potential existence, i.e. were the natural growth or increase of something already belonging to the seller. So Pothier (§ 5) recognises the sale of the expected produce of a vineyard, just as 'futures' are sold on our Cotton Exchanges. Cp. dicta as to the sale of next year's crop of apples in a specified orchard (Thacker v. Hardy (1878) 4 Q. B. Div. 685, an action for indemnity and commission on Stock Exchange contracts made by a broker for a client who was speculating on 'differences'); Watts v. Friend (1830) 10 B. & C. 446 (contract for sale of a crop of turnip seed not yet sown); Hale v. Rawson (1858) 4 C. B. 85, where a contract for the sale of tallow to be delivered on the safe arrival of a certain vessel, was held to be conditional on the single contingency contemplated, viz. the arrival of the vessel, and, the vessel having arrived with no tallow on board, the seller was found liable in damages for non-delivery.

LL. 9-11.-These three leges may be taken together, as they all deal with certain cases of mistake (error). Other passages on the same topic are LL. 14; 15; 34 pr.; 41, 1; 44; 45; 57; 58; 62, 1; and 19. 1. 21, 1.

Ulpian starts by laying down the general principle in L. 9 pr. that one of the essentials of a contract of sale is consent of the parties; but there is no real consent if the parties are not at one upon the following particulars—the legal category to which the bargain belongs, the price, or any other point (such as the person

pretio siue in quo alio, emptio imperfecta est. si igitur ego me fundum emere putarem Cornelianum, tu mihi te uendere Sempronianum putasti, quia in corpore dissensimus, emptio nulla est. idem est, si ego me Stichum, tu Pamphilum absentem uendere putasti: nam cum in corpore dissentiatur, apparet nullam esse emptionem.

1. Plane si in nomine dissentiamus, uerum de corpore constet, nulla dubitatio est, quin ualeat emptio et uenditio: nihil enim facit error nominis, cum de corpore constat.

2. Inde quaeritur, si in ipso corpore non erratur, sed in substantia error sit, ut puta si acetum pro uino ueneat, aes pro auro uel plumbum pro argento uel quid aliud argento simile, an emptio et uenditio sit. Marcellus scribsit libro sexto digestorum emptionem esse et uenditionem, quia in corpus consensum est, etsi in materia sit erratum. ego in uino quidem consentio, quia eadem prope ovoía est, si modo uinum acuit: ceterum si uinum non acuit, sed ab initio acetum fuit, ut embamma, aliud pro alio uenisse uidetur. in ceteris autem nullam esse uenditionem puto,

quotiens in materia erratur.

Now,

contracted with, or the subject-matter of the contract). one source of misunderstanding or want of agreement is the absence of true ideas (ignorance), another is the presence of false ideas (error); but as these differ only in so far as the one is negative and the other positive, they are generally discussed together under the same head of Mistake. That subject belongs to the general doctrine of contract, so that it may be assumed here that error as such has in general no legal effects at all, and it is only in exceptional cases of what is called essential or fundamental error, or error in substantialibus, that it operates to avoid an agreement. The question dealt with here is, what kind of error is inconsistent with the mutual assent required for a contract of sale?

The first case taken up is error in corpore, mistake as to the identity of the thing to be sold: if the buyer and seller had different things in view, that is fatal to the contract. It is the same in other bilateral contracts (D. 44. 7. 57), and in stipulations (D. 45. 1. 83, 1; ib. 137, 1). Even delivery will not

nature of the transaction, or about the price, or on some other point, there is no completed contract. Hence if I supposed I was buying the Cornelian estate while you meant to sell me the Sempronian, the sale is a nullity, because we are not at one as to the subject-matter. It is just the same if I believed I was buying Stichus and you intended to sell me Pamphilus, the slave not being present: we have different individuals in view, and so the sale is plainly void.

1. If we are agreed upon the subject-matter and differ only about its name, there is of course no doubt about the validity of the sale; for a mistake about the name is immaterial, if the identity is not in dispute.

2. A further question is, Whether there is a sale in cases where there is no mistake about the specific thing, but only about its nature ?—for instance, if vinegar is sold for wine, bronze for gold, lead or anything else resembling silver for silver. According to Marcellus (Digest, book vi.), the sale is valid, because the parties were agreed as to the subject sold, though mistaken about its composition. In the case of the wine I agree with him, if it has merely turned sour, for its substance is almost unchanged; but if the stuff is not wine turned, but was always real vinegar, such as we use at table, it would appear that one commodity has been sold for another. The sale is void, in my opinion, in the other cases, there being a mistake about the kind of material.

pass the property or confer possession ad usucapionem in face of such an error (D. 41. 2. 34). As to mistake about the identity of an accessory, see infra L. 34 pr. But the parties may intend the same specific thing, and give it a wrong name: that has no effect (L. 9, 1; cp. D. 45. 1. 32). Similarly, a misdescription of a person or thing in a testamentary writing is immaterial, if the identity is not in dispute, falsa demonstratio non nocet dummodo constet de persona. The mistake being in the expression merely and not in the intention, a court of law will correct it by the context, or by proper extrinsic evidence.

Again (L. 9, 2), though the parties have the same thing in