UNITED STATES SUPREME COURT DECISIONS ON-LINE

The alteration of the date in any commercial paper -- though the alteration delay the time of payment -- is a material alteration, and if made without the consent of the party sought to be charged, extinguishes his liability. The fact that it was made by one of the parties signing the paper before it had passed from his hands does not alter the case as respects another party (a surety) who had signed previously.