the State.[711] Justice Rutledge concurred without opinion. Justice Murphy, for himself and Justices Black and Douglas, thought the tax was on an essentially local activity and that the transportation through other States was "a mere geographic incident," conceding at the same time, that this view invited the other States involved to levy similar taxes and exposed the company to the danger of multiple taxation. In Memphis Natural Gas Co. _v._ Stone,[712] also of the 1948 grist, a Mississippi franchise tax, measured by the value of capital invested or employed in the State, was sustained in the case of a gas pipeline company a portion of whose line passed through the State but which did no local business there. Three Justices, speaking by Justice Reed, held that the tax was on the intrastate activities of the company in maintaining its facilities there, and was no more burdensome than the concededly valid _ad valorem_ tax on the company's property in the State. Justice Rutledge held that the tax was valid because it did not discriminate against interstate commerce nor invite multiple taxation, while Justice Black concurred without opinion. Four Justices, speaking by Justice Frankfurter, contended that the pipeline already paid the _ad valorem_ tax to which Justice Reed had adverted, and that the franchise tax must therefore be regarded as being on the interstate commerce privilege. This survey of recent cases leaves the impression that the Court is at loose ends for intermediate guiding principles in this field of Constitutional Law. The "leave it to Congress" formula is evidently in the discard, although Justice Black's successive dissents without opinion may indicate that he still thinks it sound. The multiple tax test seems to be in an equally bad way, with both Chief Justice Stone and Justice Rutledge in the grave. The concept of an apportioned tax still has some vitality however, although just how much is difficult to assess. Thus in Interstate Oil Pipe Line Co. _v._ Stone,[713] which was decided in 1949, we find Justice Rutledge, speaking for himself and Justices Black, Douglas, and Murphy, endorsing the view that Mississippi was within her rights in imposing on a Delaware corporation, as a condition of doing a local business, a "privilege" tax equal to two per cent of its intrastate business even though the exaction amounted to "a 'direct' tax on the 'privilege' of engaging in interstate commerce," an assertion which was countered by one just as positive, and also endorsed by four Justices, that no State may "levy privilege, excise or franchise taxes on a foreign corporation for the privilege of carrying on or the actual doing of solely interstate business," even though the tax is not discriminatory and is fairly apportioned between the corporation's intrastate and interstate business. The tax in controversy was sustained by the vote of the ninth Justice, who construed it as being levied only