1. Where the Goods have not been Delivered. Seller's breach of contract to sell and convey.. Specific performance not usually awarded.... Where chattel is unique....... Contracts for sale of inventions, patents or patented articles..... 1729 Specific performance not to be made substitute for damages.... 1732 Will not be granted where contract ambiguous, uncertain or un- How, when goods have neither market nor actual value........ 1744 How, when no difference between contract price and market value 1745 How, when goods to be delivered in instalments..... How, when goods to be delivered "on or before" a certain day.. 1747 How, when seller repudiates before time for performance... 1750-1753 How, when seller refuses to give credit as agreed........... 1754, 1755 Measure of damages where special circumstances were in contempla- Specific performance of agreement to deliver....... References are to sections. SALE OF PERSONAL PROPERTY. BOOK III. OF THE AVOIDANCE OF THE CONTRACT. CHAPTER I. PURPOSE AND SCOPE OF BOOK III § 798. Nature of the subjects here considered. 800. How classified. § 798. Nature of the subjects to be now considered. In the preceding chapters consideration has been given to the questions, how the contract of sale may lawfully be made, how it is to be interpreted, and what is its effect in transferring title. It is proposed now to determine how a contract of sale, actually or apparently entered into, may be avoided by one or both of the parties to it. 799. What subjects included. The class of subjects to be now considered includes those chiefly in which, while it may be admitted that a contract has in form at least been entered into, there is still opportunity for the claim that one or both of the parties is at liberty to withdraw from it upon the ground, either (1) that the supposed consent of the parties was really not given at all, or (2), if given, has been withdrawn by mutual consent, or (3) was given upon the understanding that it might be rescinded under certain circumstances, or (4) was given upon a consideration which has failed, or (5) was |