only be justified as ancillary or incidental. But even in the application of this principle to the grant of legislative power made by s. 51 (i.) the distinction which the Constitution makes between the two branches of trade and commerce must be maintained. Its existence makes impossible any operation of the incidental power which would obliterate the distinction. But the distinction between interstate and intrastate activity is not absolute. In Airlines of New South Wales Pty Ltd v New South Wales (No 2), Menzies J. noted: If control of intra-State trade is necessary to make effectual the exercise of Commonwealth power, that control may be exercised by the Commonwealth itself regardless of the control exercised by a State and regardless, too, of the fact that at some previous time the Commonwealth, because of the control exercised by a State over its intra-State trade, refrained from the full exercise of its own power. Arguments based upon the extent of State legislative power, or, the extent to which that power has been exercised, to measure or confine the legislative power of the Commonwealth, must, since the Engineers Case, fall upon deaf ears. To that end, it has been held: that s. 51(i) covers both interstate and intrastate activities where they are "inseparably connected"; but the fact that an intra-state journey may economically be required to assure the operation of an interstate service has not been sufficient to allow the Commonwealth to regulate the entirety. Intersection with Section 92 Section 92 states (in part) that: On the imposition of uniform duties of customs, trade, commerce, and intercourse among the States, whether by means of internal carriage or ocean navigation, shall be absolutely free. In the case of James v Commonwealth, which expanded on the previous ruling of the Judicial Committee of the Privy Council in James v Cowan, the High Court decided that this requirement restricted the Commonwealth Parliament as well as State Parliaments, thus greatly affecting the Parliament's authority under s. 51(i). In their judgement, Evatt and McTiernan JJ stated: We are definitely of opinion that sec. 92 lays down a general rule of economic freedom, and necessarily binds all parties and authorities within the Commonwealth, including the Commonwealth itself, because, as was pointed out by the Privy Council itself, it establishes a "system based on the absolute freedom of trade among the States" (Colonial Sugar Refining Co v Irving). Comparisons Commerce