Though, as appears from the foregoing, Congress, and to a certain extent the state legislatures as well, have the power to fix the substantive law which the federal admiralty courts are to apply, it is not within the power of these law-making bodies to determine the sphere of admiralty jurisdiction. This, it has been held, is a purely judicial function. In The St. Lawrence21 Taney declares: "Certainly no state law can enlarge the admiralty jurisdiction nor can an act of Congress or rule of court make it broader than the judicial power may determine to be its true limits. And this boundary is to be ascertained by a reasonable and just construction of the words used in the Constitution, taken in connection with the whole instrument, and the purposes for which admiralty and maritime jurisdiction was granted to the Federal Government." And in The Lottawanna case, Justice Bradley says: "The question as to the true limits of maritime law and maritime jurisdiction, is, undoubtedly, as Chief Justice Taney intimates, exclusively a judicial question and no state law or act of Congress can make it broader, or (it may be added) narrower, than the judicial power may determine those limits to be. But what the law is, within those limits, assuming the general maritime law to be the basis of the system, depends on what has been received as law in the usages of this country, and on such legislation as may have been competent to affect it" 22

18 Citing Butler v. Boston & S. S. S. Co., 130 U. S. 527; 9 Sup. Ct. Rep. 612; 32 L. ed. 1017; Norwich, etc. v. Wright, 13 Wall. 104; 20 L. ed. 585; The Lottawanna, 21 Wall. 558; 22 L. ed. 654; The Scotland, 105 U. S. 24; 26 L. ed. 1001; Providence & N. Y. S. S. Co. v. Hill Mfg. Co., 109 U. S. 578; 3 Sup. Ct. Rep. 379; 27 L. ed. 1038.

19 109 U. S. 578; 3 Sup. Ct. Rep. 379; 27 L. ed. 1038.

20 It is to be remarked that during the early period the power of Congress to legislate with reference to maritime matters was drawn from the Commerce Clause, which had been held to give federal control of navigation between the States and with foreign powers, and it was only later when the admiralty jurisdiction had been construed to extend to all public navigable waters, that the grant of judicial control over admiralty and maritime matters was resorted to as a broader source of federal control.

2U Black, 522; 17 L. ed. 180.

From the adoption of the principle that from the grant of judicial power over matters of admiralty and maritime jurisdiction, a federal legislative power is to be deduced is not to be drawn the more general rule that in all cases where federal judicial power is granted, Congress may provide the law which is to be applied in the exercise of that jurisdiction. Thus, for example, such a legislative power is not implied where the judicial power is based not upon the subject-matter in suit, but upon the character of the parties litigant.

As has been earlier shown, in suits between the States the Supreme Court from necessity finds itself obliged to determine the law applicable, which law may not be exactly the law of either of the States; so also, in suits between citizens of different States, for reasons which have been stated, the law of the States, at least as interpreted by their respective courts, is not always followed, but there has never been a suggestion that Congress might enact the law to be applied. Relations between the States of the Union being of a quasi-international character, it is eminently proper that, when necessary, general principles of jurisprudence should be applied. And where, in suits between citizens of different States, the federal courts do not hold themselves concluded by the decisions of the state courts, it is not upon the ground that federal law as distinct from state law is to be applied, but upon the doctrine that, as independent tribunals, the federal courts have a right, coordinate with that of the state courts, to determine what the state law is.

22 In the Limited Liability Act of 1851, and the Harter act of 1893, Congress has materially altered maritime liabilities as determined by general maritime jurisprudence.

In the case of admiralty and maritime causes, however, the condition is quite otherwise. Here the state courts have absolutely no jurisdiction. The general principles of the law to be applied are indeed furnished by the admiralty law of the world. But it is necessary that this body of general principles should be subject to change and addition by the legislatures of each country, and as the Supreme Court has said, it would be indeed a strange and undesirable condition of affairs to have this legislation supplied by governments whose courts have no jurisdiction to apply it.

The legislative powers of Congress thus follow ex necessitate.