pute; but, assuming for present purposes only that petitioner’s view is the correct one, the case is controlled by the settled rule that where the judgment of a state court rests upon two grounds, one of which is federal and the other non-federal in character, our jurisdiction fails if the non-federal ground is independent of the federal ground and adequate to support the judgment. This rule had become firmly fixed at least as early as Klinger v. Missouri, 13 Wall. 257, 263, and has been reiterated in a long line of cases since that time. It is enough to cite, in addition to the Klinger case, the following: Enterprise Irrigation District v. Canal Co., 243 U. S. 157, 163—165; Petrie v. Nampa Irrigation District, 248 U. S. 154, 157; McCoy v. Shaw, 277 U. S. 302; Eustis v. Bolles, 150 U. S. 361.
Whether the provisions of a contract are non-severable, so that if one be held invalid the others must fall with it, is clearly a question of general and not of federal law. The invalidity of the arbitration clause which the present contracts embody is conceded. It was held invalid by the federal district court in the Paramount case, and its judgment was affirmed here. The question, therefore, was foreclosed; and was not the subject of controversy in the state courts. In that situation, the primary question to be determined by the court below was whether the concededly invalid clause was separable from the other provisions of the contract. The ruling of the state supreme court that it was not, is sufficient to conclude the case without regard to the determination, if, in fact, any was made, in respect of the federal question. It follows that the non-federal ground is adequate to sustain the judgment.
The rule announced in Enterprise Irrigation District v. Canal Co., supra, and other cases, to the effect that our jurisdiction attaches where the non-federal ground is so interwoven with the other as not to be an independent