The original Common Law rule required a discharge by the act of the parties to be of as high a nature as the instrument to be discharged. Applying this rule to the subject of the sealed contract, it made a sealed contract or other sealed instrument essential to the discharge of a contract under seal. A subsequent oral agreement could not discharge or modify a contract under seal before breach thereof.1 Where the common forms of action and rules of pleading are still in force, and an action is brought in covenant, the entire contract relied upon must be under seal, and a subsequent oral modification of the sealed contract cannot be enforced, even after performance.2

28 Am. Rep. 22; Briggs v. Partridge, 64 N. Y. 357; 21 Am. Rep. 617; Delius v. Cawthorn, 2 Dev. Law. (N. C.) 90.

3 See Sec. 606.

4 Delius v. Cawthorn, 2 Dev. (N. C.) 90.

5 Lutz v. Linthieum, 8 Pet. (U. S.) 165.

6 See Sec. 1233.

1 Countess of Rutland's Case, Coke (Part 5), 256; West v. Blake-way, 2 M. & G. 729; Spence v. Healey, 8 Exch. 668; Smith v. Lewis, 24 Conn. 624; 63 Am. Dec. 180; Goldsborough v. Gable, 140 Ill. 269; 15 L. R. A. 294; 29 N. E. 722; Jones v. Chamberlain, 97 Ill. App. 328; Loach v. Farnum, 90 Ill. 368; Kendal v. Talbot, 1 A. K. Mar. (Ky.) 321; Brown v. Staples, 28 Me. 497; 48 Am. Dec. 504; French v. New, 28 N. Y. 147; Sherwin v. R. R., 24 Vt. 347.

2 Phillips, etc.. Co. v. Seymour. 91 U. S. 646 (decided under Illinois).

Even at Common Law a different rule applied after breach of the sealed contract, and the right of action arising therefrom could be discharged by parol.3 The original rule has, however, undergone several modifications in different jurisdictions. If the subsequent oral agreement has been performed it has been held that such performance operates as a discharge of the original contract under seal.4 In cases of this sort the oral agreement is used as a defense and is not generally relied on as the basis of an action. The difficulty caused by the technical requirements of the Common Law as to the form of action does not, therefore, arise in such cases Courts have in some jurisdictions gone farther, and have allowed a contract under seal to be discharged by a subsequent oral contract not under seal, even if not performed5 and if still executory.6 Here again the oral contract is generally used as a defense and not as a basis of action. Where no technical rule as to form of action is in force, the modern rule is that a contract under seal may be modified by subsequent oral agreement, and that an action may be brought on such contract as thus modified.7 This rule is well settled in equity8 and is recognized at law.9 A written allaw); J. C. Winship Co. v. Wine-man, 77 Ill. App. 161.

3 May v. Taylor, 6 M. & G. 261 (262, note a) ; Suyclam v. Jones, 10 Wend. (N. Y.) 180; 25 Am. Dec. 552.

4 Worrell v. Forsyth, 141 Ill. 22;

30 N. E. 673; Drury v. Improvement Co., 13 All. (Mass.) 168; Sie-bert v. Leonard, 17 Minn. 433; Me-Creery v. Day, 119 N. Y. 1; 16 Am. St. Rep. 793; 6 L. R. A. 503; 23 N. E. 198; Davis v. Inseoe, 84 N. C. 396; Reed v. McGrew, 5 Ohio 375.

5 Ryan v. Dunlap, 17 Ill. 40; 63 Am. Dec. 334; Adams v. Battle, 125 N. C. 152; 34 S. E. 245; McCauley v. Keller, 130 Pa. St. 53; 17 Am. St. Rep. 758; 18 Atl. 607.

6 Kromer v. Heim, 75 N. Y. 574;

31 Am. Rep. 491.

56

7 District of Columbia v. Iron Works, 181 U. S. 453; Canal Co. v. Ray, 101 U. S. 522; Platte Land Co. v. Hubbard, 12 Colo. App. 465; 56 Pac. 64; Tuson v. Crosby, 172 Mass. 478; 52 N. E. 744; Munroe v. Perkins, 9 Pick. (Mass.) 298; 20 Am. Dec. 475; McCreery v. Day, 119 N. Y. 1; 16 Am. St, Rep. 793; 6 L. R. A. 503; 23 N. E. 198; Homer v. Ins. Co., 67 N. Y. 478; Prouty v. Kreamer, 199 Pa. St. 273; 49 Atl. 66.

8 Canal Co. v. Ray, 101 U. S. 522.

9 District of Columbia v. Iron Works, 181 U. S. 453; Fleming v. Gilbert, 3 Johns. (N. Y.) 528; Le Fevre v. Le Fevre, 4 S. & R. (Pa.) 241; 8 Am. Dec. 696; McCombs v. McKennan, 2 W. & S. (Pa.) 216; 37 Am. Dec. 505.

teration in a sealed contract made after delivery with the assent of all the parties thereto is valid and the new provision becomes an essential part of the sealed contract.10

10Speake v. United States, 9 Cranch (U. S.) 28; Kneedler v. Anderson, 43 Ill. App. 317; Collins v. Collins, 51 Miss. 311.