commerce] to multiple tax burdens, each measured by the entire amount of the commerce, to which local commerce is not subject." The tax thus discriminated against interstate commerce; and threatened to "reestablish the barriers to interstate trade which it was the object of the commerce clause to remove."[700] The adoption by the Court of the multiple taxation principle as an exclusive test of State taxing power in relation to interstate commerce would have enlarged the former; but this was not the sole reason for its temporary vogue with the Court, or at least a section of it. Discontent with the difficulties and uncertainties of the apportionment rule also played a great part. Thus in his concurring opinion in the Gwin case, Justice Butler, speaking for himself and Justice McReynolds after showing the instability of decisions in this area of Constitutional Law, contend that "the problems of conjectured 'multiple taxation' or 'apportionment'" should be left to Congress,[701] a suggestion which Justice Black, speaking also for Justices Frankfurter and Douglas a year later, made the basis of a dissenting opinion,[702] from the doctrines of which, however, Justice Frankfurter appears since to have recanted.[703] RECENT CASES In Freedman _v._ Hewit,[704] decided in 1946, the Court held void as an "unconstitutional burden on interstate commerce" an Indiana gross income tax of the proceeds from certain securities sent outside the State to be sold. Justice Frankfurter spoke for the Court; Justice Rutledge concurred in an opinion deploring the majority's failure to employ the multiple taxation test;[705] three Justices dissented.[706] In Joseph _v._ Carter and Weekes Stevedoring Co.,[707] also decided in 1947, the Court, reaffirming an earlier ruling, held void the application of a Washington gross receipts tax to the receipts of a stevedoring company from loading and unloading vessels employed in interstate and foreign commerce, or to the privilege of engaging in such business measured by their receipts. Said Justice Reed for the Court: "Although State laws do not discriminate against interstate commerce or * * * subject it to the cumulative burden of multiple levies, those laws may be unconstitutional because they burden or interfere with [interstate] commerce."[708] This time Justice Rutledge was among the dissenters so far as interstate commerce was concerned.[709] In Central Greyhound Lines, Inc. _v._ Mealey,[710] decided in 1948, five members of the Court ruled that a New York tax on the gross income of public utilities doing business in the State could not be constitutionally imposed on a carrier's unapportioned receipts from continuous transportation between termini in the State over a route a material part of which passes through other States. Justice Frankfurter, speaking for the Court, held, however, that the tax was sustainable as to receipts apportioned as to the mileage within