IV.  When the President of the United States, or the Vice-President of the United States upon whom the powers and duties of the office of President shall have devolved, shall be impeached, the Chief Justice of the Supreme Court of the United States shall preside; and in a case requiring the said Chief Justice to preside notice shall be given to him by the Presiding Officer of the Senate of the time and place fixed for the consideration of the articles of impeachment as aforesaid, with a request to attend; and the said Chief Justice shall preside over the Senate during the consideration of said articles and upon the trial of the person impeached therein.

V. The Presiding Officer shall have power to make and issue, by himself or by the Secretary of the Senate, all orders, mandates, writs, and precepts authorized by these rules or by the Senate, and to make and enforce such other regulations and orders in the premises as the Senate may authorize or provide.

VI.  The Senate shall have power to compel the attendance of witnesses, to enforce obedience to its orders, mandates, writs, precepts, and judgments, to preserve order, and to punish in a summary way contempts of and disobedience to its authority, orders, mandates, writs, precepts, or judgments, and to make all lawful orders, rules, and regulations which it may deem essential or conducive to the ends of justice; and the Sergeant-at-Arms, under the direction of the Senate, may employ such aid and assistance as may be necessary to enforce, execute, and carry into effect the lawful orders, mandates, writs, and precepts of the Senate.

VII.  The Presiding Officer of the Senate shall direct all necessary preparations in the Senate Chamber, and the presiding officer upon the trial shall direct all the forms of proceeding while the Senate are sitting for the purpose of trying an impeachment and all forms during the trial not otherwise specially provided for.  The presiding officer may, in the first instance, submit to the Senate, without a division, all questions of evidence and incidental questions; but the same shall, on the demand of one-fifth of the members present, be decided by yeas and nays.

VIII.  Upon the presentation of articles of impeachment and the organization of the Senate as hereinbefore provided, a writ of summons shall issue to the accused, reciting said articles and notifying him to appear before the Senate upon a day and at a place to be fixed by the Senate, and named in such writ, and file his answer to said articles of impeachment, and to stand to and abide the orders and judgments of the Senate thereon, which writ shall be served by such officer or person as shall be named in the precept thereof such number of days prior to the day fixed for such appearance as shall be named in such precept, either by the delivery of an attested copy thereof to the person accused or, if that can not conveniently be done, by leaving such copy at the last known place