Supreme Court of Pennsylvania July 1, 1856 (McNair v. Commonwealth)

The opinion of the court was delivered by

Lewis, C. J.

To admit a witness to testify his belief of the handwriting of a party from having seen him write his signature only once, is to go quite far enough in support of that description of evidence. If a solitary transaction, although so slight as the subscription of a single name, have made an impression on the mind of the witness.