This section is from the book "The Law Of Contracts", by William Herbert Page. Also available from Amazon: Commercial Contracts: A Practical Guide to Deals, Contracts, Agreements and Promises.
A memorandum made upon the same piece of paper as a written contract but not intended as a part thereof, is not a material alteration ;x such as a pencil memorandum which on its face does not purport to be a part of the instrument, noting the bank where payment is to be made2 or otherwise noting the place of payment ;3 or a memorandum added to an assignment of an insurance policy to the effect that the loan for which the assignment was given was to be repaid on notice of thirty or sixty days by the assignee;4 or a memorandum written across the face of a fifteen hundred dollar note that it was to be paid to another, amount reduced to one thousand dollars.5 So a memorandum concerning interest written upon the instrument,6 as a memorandum by the payee, "I hereby agree to accept five (5) per cent annual interest on the within bond from June 1st, 1890,"7 or an indorsement made by one "who has purchased realty encumbered by mortgage, made on the note evidencing the mortgage debt, whereby he agrees to pay seven per cent interest instead of six per cent,8 is not a material alteration.
15 Young v. Borzone, 26 Wash. 4; 66 Pac. 135.
16 Gunter v. Addy, 58 S. C. 178; 36 S. E. 553.
17 Rowe v. Bowman, 183 Mass. 488; 67 N. E. 636.
1 Mente v. Townsend, 68 Ark. 391; 59 S. W. 41; State Solicitors' Co. v. Savage, 39 Fla. 703; 23 So. 413; Carr v. Welch, 46 111. 88; Light v. Killinger, 16 Ind. App. 102; 59 Am. St. Hep. 313; 44 N. E. 760; White V. Johns, 24 Minn. 387.
2 Light v. Killinger, 16 Ind. App. 102; 59 Am. St. Rep. 313; 44 N. E. 760. Apparently contra, Wood-worth v. Bank, 19 Johns. (N. Y.) 391; 10 Am. Dec. 239; a memorandum of payment being treated as prima facie a part of the contract and hence a material alteration.
3 American National Bank v. Bangs, 42 Mo. 450; 97 Am. Dec. 349.
4 Mente v. Townsend, 68 Ark. 391; 59 S. W. 41.