It was of course the natural contention of Ansett-A.N.A. that T.A.A. required a licence under the Tasmanian legislation but could not have one for the reasons disclosed in its notice of appeal to the Public Vehicles Licensing Appeal Tribunal. On the other hand, it was the natural contention of T.A.A. that it could operate without a licence notwithstanding that it had obtained one which of course it sought to retain. This curious situation was dealt with by the Tribunal in a judgment which in effect held that T.A.A. possessed under s. 19A of the Commonwealth Act authority without any State licence to establish and carry on the service and that therefore there was no foundation for the appeal. In effect the judgment said that the main argument of the appellant was that the State of Tasmania had not validly referred a matter, viz. air transport, to the Commonwealth under s. 51 (xxxvii.) of the Australian Constitution by reason of the reference to the Commonwealth being revocable (s. 3 of the Commonwealth Powers (Air Transport) Act 1952 of Tasmania) and it would follow that s. 19A of the Australian National Airlines Act 1945-1961 is invalid and for that reason failed to empower the Airlines Commission (T.A.A.) to operate Tasmanian intra-State air services during the period of the operation of any State Act which has referred the matter of air transport or the regulation of air transport to the Commonwealth. The conclusion of the Appeal Tribunal was as expressed in this paragraph of its reasons: "The Tribunal therefore is of the opinion that a matter may be referred by a State under s. 51 (xxxvii.) of the Commonwealth Constitution otherwise than irrevocably, that the Commonwealth Powers (Air Transport) Act 1952 is within the legislative power of the State of Tasmania and that s. 19A of the Australian National Airlines Act 1945-1959 is a valid exercise by the Commonwealth Parliament of its legislative powers." The Tribunal was satisfied, according to the reasons, "that none of the regulatory provisions, including licensing, of the Traffic Act regarding the use by the Commission (T.A.A.) of aircraft as public vehicles in this State are applicable in the case of aircraft operated by the Commission (T.A.A.) under the powers conferred on it by s. 19A." The reasons concluded: "In the view of the Tribunal the appeal should be and is struck out." This meant that the tribunal disposed of the appeal by deciding that a licence for T.A.A. was unnecessary having regard to the operation of s. 19A of the Australian National Airlines Act 1945-1961. It is to be noticed that s. 19A (1) according to its terms operates only where the Parliament of a State has by a State Act referred to the Parliament of the Commonwealth the matter of air transport or the matter of the regulation of air transport. It would be useless therefore to say that that was intra vires because the operation of the external affairs power would support a provision not so justified, assuming that to be so. Three points are taken against the operation of s. 19A to relieve T.A.A. of the necessity of obtaining a licence under the Traffic Act 1925 as amended up to and including the Traffic Act (No. 31 of 1961). The material provision of the enactment thus amended is that no person shall drive or use or cause or permit to be driven or used as a public vehicle any vehicle in respect of which a licence is not in force: s. 24 (1) III as amended. The first is that, assuming that s. 19A of the Australian National Airlines Act 1945-1961 has an operation, it does no more than confer a capacity upon the Commission (that is T.A.A.) so that it is not ultra vires for it to operate an airline service within Tasmania: the section does not empower the Commission to do so. The second is that as a matter of construction s. 19A (1) does not purport to enable or authorize T.A.A. to use a public vehicle, which by definition includes an aircraft, except subject to State law. Thirdly the appellant relied on a contention that s. 19A was ultra vires because the Commonwealth possessed legislative power over no subject matter which would authorize it and in particular the operation of s. 51 (xxxvii.) of the Constitution upon the subject-matter referred by the Commonwealth Powers (Air Transport) Act 1952 did not provide such a subject-matter. The first two of these three contentions of course are concerned with the operation of s. 109 of the Constitution to displace the application to or operation upon T.A.A. of s. 24 (1) III of the Traffic Act 1925-1961 of Tasmania. They do not, however, depend on the meaning or interpretation of s. 109 but upon the meaning and effect of s. 19A of the Australian National Airlines Act 1945-1961. Section 19A is expressed in language which when the required conditions are fulfilled is not inappropriate to authorize the Commission (T.A.A.) to establish airline services for the transport for reward of passengers or goods within that State and to maintain and operate airline services for any such transport. There is no reason for treating the provision as concerned only with what shall be within the scope of the Commission's corporate capacity, as concerned only with defining what shall be a juristic act of the Commission. The words used do not read as if they were simply facultative, as meaning to do no more than confer a capacity upon a statutory corporation so that it would be within its corporate powers to do the thing thereby specified. Indeed sub-s. (1) goes on to say: "and shall have, in relation to any such service, the like powers as it has in relation to airline services specified in sub-s. (1)" of s. 19. As has already been said s. 19 describes the general functions and duties of the Commission and is enacted under the commerce power as well in part perhaps as under the power over postal services. It should be pointed out that under sub-s. (2) of s. 19A a notification by the Premier of the State of Tasmania to the Prime Minister of the former's consent to the establishment of the service is necessary to enable the Commission lawfully to establish it. Under sub-s. (2) (b) the continuance of the consent is necessary for the continuance of the service. So that if the Premier notifies the withdrawal of his consent to the operation of the service the Commission shall not continue it. Why then should s. 19A be construed as enabling T.A.A. to establish, and to maintain and operate, airline services of the kind described but only subject to the licence or permission of State law? The answer must be that neither in the text nor the context nor in any matter of implication or inference can any reason for such a construction be found. But if it were correct that s. 19A should as a matter of interpretation be treated as facultative it remains nevertheless difficult to see why (under s. 109) T.A.A. should be able only to exercise its capacity under or subject to s. 24 sub-s. (1) III and sub-s. (13) of the State law (Traffic Act 1925-1961). The Tribunal however took the view, so the counsel of Ansett-A.N.A. said, that T.A.A. could lawfully operate in Tasmania and in disregard of Tasmanian law, without a licence under Tasmanian law; that s. 19A produced an inconsistency with that law and the appeal should therefore be struck out. Since T.A.A. did not need a State licence the appeal against the issue of such a (superfluous) licence should be treated as outside the purview of the Tribunal's functions. Unless therefore s. 19A of the Australian National Airlines Act 1945-1961 of the Commonwealth is inoperative or ineffectual, as by its third contention Ansett-A.N.A. maintains, it would seem that the Tribunal correctly held that T.A.A. could carry on its services on the routes within the confines of Tasmania without a licence under the Traffic Act 1925 as amended and as affected by the Transport Act 1938 and the subsequent amendments of that Act and by the Traffic Act 1961. And there is no reason to think that the Tribunal was wrong in treating that conclusion as disposing of the purported appeal before it. It has already been pointed out that s. 19A must of course, having regard to its terms, be considered as depending on s. 51 (xxxvii.) of the Commonwealth Constitution. Section 51 (xxxvii.) provides that the Parliament (of the Commonwealth) shall, subject to the Constitution, have power to make laws for the peace, order and good government of the Commonwealth with respect to matters referred to the Parliament of the Commonwealth by the Parliament or Parliaments of any State or States, but so that the law shall extend only to States by whose Parliaments the matter is referred or which afterwards adopt the law. The "matter" in respect of which s. 19A was enacted seems undeniably to be that set out or described in the Tasmanian Commonwealth Powers (Air Transport) Act 1952 (No. 46 of 1952). Unless that statute fails to achieve its intended purpose s. 19A must, as would appear, constitute a valid law of the Commonwealth. A number of reasons, however, have been assigned on behalf of Ansett-A.N.A. for saying that the Tasmanian Act (No. 46 of 1952) cannot fulfil its purpose. Some of these provide alternative grounds for the conclusion and are inconsistent; others are cumulative. It will be convenient to deal with the grounds in a different order from that in which they were presented in argument.