tion, elicit the witness' knowledge as to facts that constitute part of the opponent's own case, or whether he is confined to the matters already dealt with in the direct ex amination, or, at least, to topics connected therewith. (a) In England, and in the United States down through the first quarter of the iSoos, there was apparently but one view upon this subject. There seems, indeed, to have been no question at all; so that in English judi cial opinions an express statement of the rule is scarcely to be found. That rule— which may be termed the orthodox one— adopted the former of the above alterna tives. (b) But in the year 1827, Chief Justice Gibson of Pennsylvania, in dealing with a related point, chanced to remark (without citing an authority) that, as the ordinary rule, the cross-examining party should not "prove his case by evidence extracted on cross-examination," and also that a witness may not be cross-examined to facts which are "wholly foreign to what he has already testified." . . . Original Form of the Federal Rule. Be fore considering the respective policies of these opposing rules, it is necessary to keep in mind that in their original form they were never put forward by their eminent spon sors [Gibson, C. J., and Story, J..] as any thing but rules of customary and normal practice, subject always to the general prin ciple that the trial Court may, in its discre tion, allow exceptions. Chief Justice Gibson, the very progenitor of the Federal rule, de clared radically that he "would not, without further consideration, pronounce the exer cise of the discretion, depending as it does upon circumstances which cannot be fully made to appear in a court of error, to be a legitimate subject of a bill of exceptions." In the Pennsylvania and the Federal Su preme Courts—the two most notably asso ciated with this rule—this controlling prin ciple of discretion has from time to time been expressly emphasized. . . . But, un fortunately, this same qualification, always assumed by the inventors of the rule as an inseparable part of it, has usually been lost
sight of by their followers—at least among the adherents of the Federal rule. Yhile seldom expressly denying the principle of discretion, they have come practically to ignore it. ... Furthermore, the rule has suffered degen eration in another respect, in the hands of most of its modern adherents. For it would seem that both of the eminent judges, Gib son and Story, who promulgated it, under stood it to exclude only the putting in of the opponent's own case-—;. c., the new facts constituting his affirmative defense (whether strictly appropriate to an affirmative plea or not); yet their language made it possible for their followers to forbid an examination to anything but the precise matters testified by the witness on the direct examination, even to matters which properly concerned the calling party's own case under the allega tions of his pleading. IN an interesting article in the Virginia Law Register on "Federal Common Law," Hunsdon Cary, of the Richmond Bar. holds that, without question, "the Federal Courts have no common law criminal jurisdiction," but that "both on principle and authority there is a recognized Federal common law in civil cases." As to Wheaton v. Peters, 8 Pet. 658, and Smith r. Alabama, 124 U. S. 478, which are usually cited as denying the latter proposition, the author maintains that the parts of those opinions bearing on the point in question are obiter dicta. In support of the proposition that there is a Federal common law in civil cases he cites a few of the more important cases, relying especially on Murray г1. Chicago and N. W. Ry.. 62 Fed. Rep. 24, quoting from Mr. Justice Shiras' able opinion in that case, as follows: We cannot better conclude our position on the question of Federal common law than by adopting the language of Judge Shiras as our own: "The true doctrine, in my judgment, is that the Constitution of the United States, when it was adopted, gave full recognition to the existing systems of the law of nations, of admiralty and mari time, of the common law, and equity. It ap portioned to the national government, then
