A written contract can not prove itself. The genuineness of the signatures and the execution and delivery of the contract, which are essential to its validity,1 must be proved by extrinsic evidence, and if all extrinsic evidence of the facts of execution were to be excluded, a written contract could not be shown to be valid. The so-called parol evidence rule has, therefore, no application where the issue is whether or not the contract sued upon was entered into, and the evidence is offered for the purpose of showing that no contract was in fact made.2 Extrinsic evidence is admissible to show what took place at the execution of the instrument, as far as such facts affect its validity.3

Iowa. Brennecke v. Heald, 107 Ia. 376, 77 X. W. 1063.

Michigan. Church v. Case, 110 Mich. 621, 68 N. W. 424.

Washington. Reiner v. Crawford, 23 Wash. 669, 83 Am. St. Rep. 848, 63 Pac. 516.

Wisconsin. Manufacturers' & Merchants' Inspection Bureau v. Everwear Hosiery Co., 152 Wis. 73, 42 L. R. A. (X.S.) 847, 138 X. W. 624.

1See Sec. 1173 et seq.

2 Northern Trust Co. v. Bruegger, 35 N. D. 150, 159 N. W. 859.

3 United States. Beach v. Nevins, 162 Fed. 129, 89 C. C. A. 129, 18 L. R. A. (N.S.) 288.

Alabama Tumlin v. Tumlin, 195 Ala. 457, 70 So. 254.

Illinois. Jordan v. Davis, 108 111. 336; Shipley v. Shipley, 274 111. 506, 113 N. E. 906.

Iowa. Garner v. Kratzer, 173 Ia. 292, 155 X. W. 296; Franke v. Kel-sheimer, 180 Ia. 251, 163 N. W. 239.

Kansas. Morris v. Blazer, 96 Ivan. 466, 152 Pac. 767.

Kentucky. Williams v. Hall, 32 Ky. (2 Dana) 97.

Massachusetts. Bowes v. Christian,

222 Mass. 359, 110 X. E. 1034; Hinden-lang v. Mahon, 225 Mass. 445, 114 N. E 684.

Michigan. Wilbur v. Stoepel, 82 Mich. 344, 21 Am. St, Rep. 568, 46 X. W. 724; Woodard v. Walker, 192 Mich 188, 158 X. W. 846.

Minnesota. Grimes v. Minneapolis, St. Paul, Rochester & Dubuque Electric Traction Co., 133 Minn. 442, L. R. A. 1916F, 687, 158 X. W. 719.

Oklahoma. Rutherford v. Holbert, 42 Okla. 735, L. R. A. 1915B, 221, 142 Pac. 1099; Waggoner Bank & Trust Co. v. Doak, - Okla. - , 172 Pac. 61; , J. M. Hoard, Jr., Co. v. Grand Rapids Showcase Co., - Okla. - , 173 Pac. 844.

Pennsylvania. Johnson v. Smith, 165 Pa. St. 195, 30 Atl. 675; Excelsior Saving Fund & Loan Association v. Fox, 253 Pa. St. 257, 98 Atl. 593.

Texas. McCartney v. McCartney, 93 Tex. 359, 55 S. W. 310 [reversing, 53 S. W. 388].

Washington. Hindle v. Holcomb, 34 Wash. 336, 75 Pac. 873; Garring v. Stephens. - Wash. - , 184 Pac. 314.

West Virginia. Flowers v. Fletcher, 40 W. Va. 103, 20 S. E. 870.

Since a deed does not prove its own execution or delivery, extrinsic evidence of the facts of execution and delivery is admissible, as such evidence does not contradict the terms of the instrument, but on the contrary, tends to show whether or not the instrument ever took effect.4 If the real question in issue is whether the offer was accepted in a reasonable time or not, the purpose for which the written offer was made may be shown in order to determine whether the acceptance was made within a reasonable time.5

If the real question in dispute is as to the time at which the contract was made, prior written negotiations are admissible for the purpose of proving such fact.6 If a written contract was delivered in escrow, extrinsic evidence is admissible to show the terms of the escrow agreement, and whether the contract was delivered in accordance with the terms of such escrow agreement.7 Evidence which bears on the genuineness and authenticity of the signature of a party to a written contract is admissible.8 If A signs a contract by his mark, and the name which is written by such mark is not A's real name, extrinsic evidence is admissible to explain such form of signature.9 Extrinsic evidence is admissible to show whether terms which are not written in the body of the contract,10 such as terms which are written under the signature of one of the parties,11 were intended by the parties as terms of the contract. If A denies that he ever assented to the written contract alleged by B, A may show the oral contract which, as he claims, was the only contract entered into.12 If a written contract is in form an offer by A, accepted by B in writing, it may be shown that B accepted it in writing before A agreed to it or signed it, and hence that it was really B's offer.13 If a clause in a written contract executed by an agent makes it subject to the approval of the principal, it may be shown that the principal assented to such contract in advance.14

Wisconsin. Curry v. Colburn, 99 Wis. 319, 67 Am. St. Rep. 860, 74 X. W. 778.

4Tumlin v. Tumlin, 195 Ala. 457, 70 So. 254; Shipley v. Shipley, 274 111. 506, 113 N. E. 906; Morris v. Blazer, 96 Kan. 466, 152 Pac. 767; Garry v. Stephens, - Wash. - , 184 Pac. 314.

5 Philips v. Newoc Co., 101 Wash. 234, 172 Pac. 355.

6 Hamilton Iron & Steel Co. v. Grove-land Mining Co., 233 Fed. 388, 147 C. C. A. 324.

7 Northern Trust Co. v. Bruegger, 35 N. D. 150, 159 N. W. 859.

8 Bachinsky v. Federal Coal & Coke Co., 78 W. Va. 721, 90 S. E. 227.

9 Bachinnky v. Federal Coal & Coke Co., 78 W. Va. 721, 90 S. E. 227.

10 Leahmer v. McCollough, 99 Kan. 451, 162 Pac. 297.

11 Leahmer v. McCollough, 99 Kan. 451, 162 Pac. 297.

12 Brennecke v. Heald, 107 Ia. 376, 77 N. W. 1063.

13 Elastic Tip Co. v. Graham, 174 Mass. 507, 55 N. E. 315.