Briefs on appeal.
Section 70
SEC. 70. Briefs on appeal.—Upon receipt of the answer to the petition or upon conclusion of the presentation of additional evidence, the clerk of the Supreme Court shall notify the parties, and the petitioner, within thirty days from such notice, shall file twenty copies of his brief upon the adverse parties and, within thirty days from such service, the adverse parties shall file twenty copies of their brief together with proof of service of five copies thereof upon the petitioner.