In this Act, if not inconsistent with the context, the following expressions have the meanings herein-after respectively assigned to them:
“Great Seal” means the Great Seal of the United Kingdom:
“Document to which this Act applies” means any writ, commission, letters patent, letters close, or document of such a character, or belonging to such a class, as would at the date of the passing of this Act, be required to be or usually would be authenticated by being passed under the Great Seal:
“Crown Office” means the office of the Clerk of the Crown in Chancery.