-403§ 3071. Questions of fact and law (a) All questions of fact, other than those mentioned in subsection (b) of this section, are to be decided by the jury, when the trial is by jury, and all evidence thereon is to be addressed to them, except when otherwise provided by this title. (b) All questions of law, including the admissibility of testimony, the facts preliminanr to its admission, and the construction of statutes and other writmgs, and other rules of evidence, are to be decided by the court, and all discussions of law addressed to it. (c) The provisions contained in this title respecting the evidence on a trial before a jury, are equally applicable on the trial of a question of fact before a court, referee, or other officer. Subchapter II—Writings Generally § 3101. Kinds of writings Writings are of two kinds: (1) public; and (2) private. § 3102. Public writings defined Public writings are: (1) the written acts or records of the acts of the sovereign authority, of official bodies and tribunals, and of public officers, legislative, judicial, and executive, whether of the Canal Zone, of the United States, of a State of the Ignited States, or of a foreign country; and (2) public records, kept in the Canal Zone, of private writings. § 3103. Private writings defined All writings other than those defined by section 3102 of this title are private. § 3104. Explanation of altered writings The party producing a writing as genuine which has been altered, or appears to have been altered, after its execution, in a part material to the question in dispute, shall account for the appearance or alteration. H e may show that the alteration was made by another, without his concurrence, or was made with the consent of the parties affected by it, or otherwise properly or innocently made, or that the alteration did not change the meaning or language of the instrument. If he does so, he may give the writing in evidence, but not otherwise. Subchapter III—Public Writings § 3121. Classification of public writings Public writings are divided into four classes: (1) laws; (2) judicial records; (3) other official documents; and (4) public records, kept in the Canal Zone, of private writings. § 3122. Written laws defined A written law is that which is promulgated in writing, and of which a record is in existence. ^ § 3123. Public and private statutes defined Statutes are public or private. A private statute is one which concerns only certain designated individuals, and affects only their private rights. All other statutes are public, in which are included statutes creating or affecting corporations.