In the primary sense of the word, a witness is a person who has _knowledge of an event. As the most direct | mode of acquiring knowledge of an eventis by seeing it, “witness” has acquired the sense of a person who is present at andobserves a transaction. Sweet See State v. Desforges, 47 La. Ann. 1167, 17 South. 811;In re Ix>-U see’s Will, 13 Misc. Rep. 298, 34 N. Y. Supp. 1120; Bliss v. Shuman, 47 Me. 248.A witness is a person whose declaration under oath (or affirmation) is received asevidence for any purpose, whether such declara-Vtion be made on oral examination or by deposition or affidavit Code Civ. Proc. Cal. {1878; Gen. St. Minn. 1878, c. 73,