Counsellors who are associated with those regularly retained in a cause, either for the purpose of advising as to the points of law involved, or preparing the case on its legal side, or arguing questions of law to the Court, or preparing or conducting the case on its appearance before an appellate tribunal, are said to be “of counsel.” 2. Knowledge. A grand jury is sworn to keep secret “the commonwealth’s counsel, their fellows’, and their own.” 3. Advice given by one person to another in regard to a proposed line of conduct, claim, or contention. State v. Russell, 83 Wis. 330, 53 N. W. 441 ; Ann. Codes & St. Or. 1001,