regulating the taking up of lands within the new purchase, of which the 13th section expressly excepts islands in the Ohio, Allegheny and Delaware.

"This being the navigable character of the stream, the rights of the riparian owners are settled by numerous decisions, a few of which may be referred to: Carson v. Blazer, supra; Shrunk v. Schuylkill Nav. Co., supra; Ball v. Slack, 2 Whart. 508; Zimmerman v. Union Canal Co., 1 W. & S. 346; Bailey v. Miltenberger, 7 Casey, 37; McKeen v. Delaware Div. Canal Co., 13 Wright, 424; Tinicum Fishing Co. v. Carter, 11 P. F. Smith, 21, opinion by Sharswood, J., decided last winter at Philadelphia. From these and other cases, it will appear that the absolute title of the riparian proprietor extends to high-water mark only, and that between ordinary high and ordinary low water-mark, his title to the soil is qualified, it being subject to the public rights of navigation over it, and of improvement of the stream as a highway. He cannot occupy to the prejudice of navigation or cause obstructions to be placed upon the shore between these lines, without express authority of the state.

"The case of Bailey v. Miltenberger, 7 Casey, 37, decided in 1856, doubtless had something to do in turning public attention to the shores of the streams surrounding the city of Pittsburg, which led to the passage of the Act of 1858, for the purpose of defining the low and high waterlines. It referred to the mistaken idea entertained by some proprietors of making ground for their mills, by depositing cinders on the shore between low and high water marks. "The Allegheny and many other navigable rivers' (says the opinion) 'do not, at the time of low water, occupy over one-third of their bed; and it would be most disastrous to allow every owner to fill out his land to low water-mark.' This state of affairs, for these rivers had been seriously encroached upon at and opposite Pittsburg,

no doubt led to the Act of 16th April, 1858, Pamph. L. 326. It begins by a recital, 'Whereas, The lines of lands on and along the shores at the rivers at and near the city of Pittsburg, in the county of Allegheny, have never yet been clearly ascertained, and as it is important to the owners of such lands, the persons navigating the waters of, and the corporations adjacent to, such rivers, and to all parties interested, to know and to have their several rights and privileges in extension and limitation ascertained and defined; therefore,' &c. The first impression arising from this language might seem to be that the law was intended to ascertain and fix these high and low water lines to end all controversies, private as well as public. But a careful consideration of its purpose and provisions shows that it is not applicable to disputed boundaries between private owners, but was intended to regulate the respective rights of the public and the landowners, over whose property the right of navigation extends between high and low water lines.

"The effect of the lines as established is thus stated: 'the lines so approved shall for ever after be deemed, adjudged and taken, firm and stable for the purposes aforesaid.' If we seek for the 'aforesaid' purposes, the act discloses none but those relating to the public interest and that of the riparian owner. Then if we advert to the power of the state over navigable streams, as stated in the authorities cited, we discover that it is plenary over the subject of navigation and the improvement of these natural channels of commerce, while the ownership of the riparian proprietor is qualified between the lines of low and high water. The legislature may, therefore, with great propriety define the bounds of high and low water, by means of a suitable commission, for the purpose of regulating the public right, so as not to conflict with private interests, and to prevent private rights from being exercised

to the prejudice of public interests; for example, to prevent the shores from being filled up with great banks of cinders."

In Allegheny City v. Moorehead (1875), supra, the question was presented whether by the fixing of water lines under the act of 1858, title had been vested in the city of Allegheny or lot owners, so as to defeat the claim of the plaintiff Moorehead under a subsequent patent from the State. The court said (p. 139): "Nor can the operation of the Act of 1858 be extended by the act of the commissioners in running out the low-water line of the northern shore of the river to include a part of what was Killbuck island. It was not the purpose of the commissioners to transfer titles, but to mark the boundaries of riparian rights, so as to make them certain and permanent in their extent. So it was not the intention of the framers of the Act of 1858 to pass titles to lands, or to ascertain boundaries between individuals; but it was their purpose to regulate the right of navigation along the shores of these rivers by establishing high- and low-water lines, which would definitely ascertain and fix the extent to which the right could be exercised; and the extent to which the owners of the land could exercise their own rights under the law of the state."

It is contended for the complainant that the effect of the statute was to secure to riparian owners complete protection against any loss of their land, or of the right to build upon it, by reason of the gradual washing away of the banks of the river; that the State chose to resign to the riparian proprietors its right to such additions from the moving landward of the low-water mark, and required the owner at the same time to surrender in the interest of navigation his right to alluvion. In support, the complainant cites the opinion of, the Court of Common Pleas No. 2 of Allegheny County in Briggs v. Pheil (1894), 42 Pittsburgh Legal Journal, p. 18, in which it is said with respect to the same statute: "At the passage of this act

223 U.S.

Opinion of the Court.

the riparian owner owned absolutely to high water mark, and had a qualified property to low water mark, and outside of the low water mark the title to the soil was in the State. It seems to us there can be no doubt that the State had power to enact that thereafter the legal limits of the property should remain unchanged, either by gradual accretions or by gradual cutting away. This in our opinion was intended to be done and was done by the Act of Assembly and the proceedings thereunder.

It seems to us that the establishing of these lines, at least, as between the State and riparian owners, fixed the lines for the future. If the river washes in beyond the high water line the owner may fill up and reclaim the lost land, and on the other hand accretions belong to the State or the municipalities."

The established doctrine is invoked that the title to the soil under navigable waters within their territorial limits, and the extent of riparian rights, are governed by the laws of the several States, subject to the authority of Congress under the Constitution of the United States. Martin v. Waddell, 16 Pet. 367; Pollard v. Hagan, 3 How. 212; Weber v. Harbor Commissioners, 18 Wall. 57; Barney v. Keokuk, 94 U. S. 324, 338; Packer v. Bird, 137 U. S. 661, 669; St. Louis v. Rutz, 138 U. S. 226, 242; Hardin v. Jordan, 140 U. S. 371, 382, 402; Illinois Central R. R. Co. v. Illinois, 146 U. S. 387, 435, 452; Shively v. Bowlby, 152 U. S. 1, 40-47; Water Power Co. v. Water Commissioners, 168 U. S. 349, 365. Let it be assumed that the Pennsylvania statute in its regulation of rights, established the Commissioners' high-water line as the permanent boundary of the island and conferred upon the riparian owner, so far as it was within the competency of the State to confer it, the right to fill in and to erect structures to the limit of this line, regardless of subsequent changes in the actual high-water line caused by the washing away of the banks of the river. What, then, was the power of Congress with

respect to the river and what was the extent of the authority conferred upon the Secretary of War?

When the Secretary of War, in 1895, fixed harbor lines he dealt with the stream as it then existed. Whatever right the owner of the island may have had under the state law to reclaim the submerged land within the former line of high water, had not been exercised. The bill, in alleging that the new harbor line ran across the complainant's land, must be taken to refer to the submerged land already described. This is the import of its allegations and is shown by the record of the War Department annexed to the bill. In establishing this line, the Secretary of War followed quite closely the actual line of high water as it existed in 1895, except in the back channel of Brunot's Island where it ran several hundred feet outside the then high-water mark. The change of the harbor line at this point, in 1907, was for the purpose of making the line coincide with the actual high-water mark and in the report of the United States engineer who advised the change it was said that the lines as previously established had "not been filled out to, and the river bed on the Brunot Island side, and in the bend referred to" was in "essentially the same condition" as at the time the harbor lines of 1895 were fixed. He added:

"Pittsburgh suffers annually from floods and in my opinion any material contraction of the channel immediately below the city would result in general injury and would produce conditions detrimental to navigation and to harborage, and it is respectfully recommended that the changes in the established harbor lines shown and described on the map inclosed herewith be made, such changes being necessary in preserving and protecting the harbor of Pittsburgh.

"The location of the proposed harbor lines recommended in this communication is within the bed of the stream as it exists as a physical fact."