The Constitution s 76(iii) enables the Parliament to make laws conferring original jurisdiction on the High Court in any matter “of Admiralty and maritime jurisdiction”. This provision was copied directly from art 111 s 2(1) of the Constitution of the United States. One issue has been whether s 76(iii) is limited to what was within the jurisdiction in 1901. Another, however, has been whether it confers a substantive power in the power to confer jurisdiction – that is power to legislate on admiralty and maritime law generally. Cases on art 111 s 2(1), and the reasoning they adopt, suggest it does. But is such reasoning applicable to s 76(iii)? Are there countervailing considerations, indicating to the contrary, that s 76(iii) (even if implying a body of law) is no more than merely a power for “the conferment of jurisdiction in a particular class of controversies”? These are significant questions in Australian constitutional law.