(b) Artificial coastlines. Except for the 10-mile rule for bays and estuaries," the use of artificial base lines (usually arbitrary straight lines), should be very limited. It is suggested that, except where they are regarded as having been established by prescription, they be understood to be effective only when interested states, or the international community, specifically accepts the claims of the coastal state. It is true that man requires definiteness and that nature usually discloses gradualness of transition. But the outer limits of the territorial sea and of any contiguous zones are fully as specific and continuous, when delimited only from all points on the low-tide coastline, including islands, as explained in the preceding section, as they can be if based, in part, on straight arbitrary base lines.

(c) Definition of "island" (in relation to base line problems). All ordinary islands (i. e., not wholly submerged at high tide) have the normal belt of territorial sea. Question arises whether a low-lying "island" (mudflat, rock, etc.), which is covered at high tide and dries only at low tide, shall be regarded as an island entitled to its own belt of territorial sea.

Without going into the complicated question further and citing numerous references, the writer favors the rule adopted by Sub-Committee No. II (the "Technical Sub-Committee”) at the Hague Codification Conference, 1930, namely: "Elevations of the sea bed situated within the territorial sea [italics supplied], though only above water at low tide, are taken into consideration for the determination of the base line of the territorial sea." 28

Any elevation of the sea bed that dries at low water, in case it lies within the T-mile limit of mainland or of other bona fide islands (never covered by the tide) is thus regarded as an "island" and is accorded a belt of territorial sea measured from its own low-tide line. But if such a problematical island lies outside the territorial sea delimited from the mainland or from a never-covered island, it shall be disregarded in delimiting the territorial sea and shall have no belt of its own.

Geological history of a coastal region is sometimes adduced as if the shorelines of tens of thousands, even millions of years ago, might be taken into account in modifying the present low-water datum in water area delimitation. Certainly geological history, where fully deciphered, explains present shorelines, the presence and availability of minerals, and the distribution of banks and shoals, some of which are good fishing areas. Recalling that there are established rules relating to gradual or sudden changes of river courses (accretion or avulsion) in boundary matters, the supposed option of citing the geological past, when it appears to serve one's purpose, in order to advance seawardly the base line in delimiting the territorial sea, seems to constitute an extraordinary type of special pleading.

3. Outer Limits of Inland Waters

The principles and techniques relating to "Bays and estuaries," involving both definition and delimination, which were proposed by the United States Delegation at The Hague, 1930, as they were explained by the writer in this JOURNal (Vol. 24 (July, 1930), pp. 548-552, and Figs. 3, 4 and 5), do not seem to require revision. The fact may be emphasized that, if the T-mile 'envelope of arcs" were initially described on the charts, and if there were any islands in front of a gulf or bay (as in Fig. 3 (b) referred to above), no delimitation of the outer limit of inland waters would be required in order to determine the seaward limit of the territorial sea.

Where there are numerous islands, as along parts of the coasts of Maine, or Norway (Fig. 1, above, page 545), the territorial sea may be much more than Tmiles in width between the seaward limit and the mainland. Usually the re

to islands; and isolated mudflats that entirely cover at high tide appear as “islands” in this special color. This is the ideal type of chart from which to delimit the territorial sea where precise delimitation is desired-because the low-tide line is clearly indicated. But in almost all parts of the world the strip of land that covers and uncovers with the tide is so narrow that it is scarcely mappable at the scales of ordinary hydrographic charts, frequently not being much wider than the width of a line on the printed chart. The low-water base line from which the territorial sea is delimited is therefore usually not shown on published charts.

A series of tide tables, giving predictions for a year, is published annually by the U. S. Dept. of Commerce Coast and Geodetic Survey, which covers the world in 4 volumes, Typical tide curves are shown in the introductory pages, and provide graphic illustration of the very great differences in the characteristics of tides in different parts of the world. See this Journal, Vol. 24 (July 1930), pp. 550-551, and Fig. 5 (p. 547).

Report of the Second Commission (Territorial Sea) [L. of N. Doc. C.230.M.117.1930.V.],

p. 11.

gime of the territorial sea, for example, innocent passage, is assumed to apply to the entire belt of water, regardless of width.

There are some stretches of coast, however, where the screen of numerous islands or the exceptional sinuosities of the mainland shoreline would seem to justify, if not to require, regarding part of the waters nearest the mainland as "inland waters" even though there is no approximation to a "bay" as hitherto considered in the delimitation of the territorial sea. And because jurisdictional limits should be precise, and techniques may be needed in cases involving international law, a hypothetical situation is discussed here.

The problems presented on Figure 2 constitute a geographical composite of problems encountered in several specific areas, which can be most succinctly discussed in connection with this hypothetical example. The numerous small indentations of island and mainland coastlines illustrated are of such configuration that, if they were ten times as large, they would constitute “bays" and would present a very different type of problem. In view of the very unusual nature of the geographical-geometrical problem presented, a slight extension of the method of delimination recommended in 1930 as of universal applicability seems to the writer to be called for.

For the exceptional type of geographical situation here encountered the following principles seem to be applicable:

sea.

1. The outer limit of the territorial sea should be exactly the same as if all the recessed waters were part of the territorial sea instead of partly inland waters. That is, the seaward limit should constitute the envelope of arcs of all circles of 3-mile radius drawn from all points on the coast, including islands, and from only those straight line "artificial coasts" that are justified by the definition of "bays and estuaries" proposed in 1930.29

2. The territorial sea should everywhere have a minimum width of 3 miles. 3. Where islands lie between inland waters and the territorial sea (e. g., "Fish I.," on Fig. 2), the outer limit of inland waters is the low-water shoreline on the landward side.

As illustrated in Figure 2 and explained beneath, the envelope of 3-mile arcs is first laid down on the chart, constituting the seaward limit of the territorial The unique feature in this problem is that the only way to provide the minimum width of 3 miles for the territorial sea in some areas is to describe reverse 3-mile arcs, centered at the points of intersection of the arcs comprising the seaward limit of the territorial sea. Actually it provides a simplified artificial coastline that may, in some instances, be more satisfactory than an exceptionally irregular coastline.

Another type of problem is illustrated between point E and F, on "Bird Island" and "Fish Island," which are shown here as more than 6 miles apart. In order to provide a full 3-mile belt of territorial sea, the inland waters' outer limit would usually have had to lie at least 3 miles inland, and would therefore constitute 3-mile arcs from E' and F", joined by a straight line equal to E'F" and parallel to it, as represented by broken lines in Figure 2. But the fact that the relationship of Fish and Bird Islands to the main group of islands to the south produces an objectionable "pocket of high sea," west of the line AB, calls for the assimilation of that pocket by the territorial sea, so that the line EF would here properly serve as part of the outer limit of inland waters.

4. Median Lines-Techniques of Delimitation in Gulfs, Lakes, etc.

In inland waters, where an international boundary traverses a river or a lake, the boundary may be defined as following either the thalweg (a vertical crosssection concept, properly applicable only if there be a navigable channel) or the median line (a horizontal-plane concept).

In gulfs, lakes and seas, the median line may constitute either: (a) a portion of an ordinary boundary (as in Lake Erie); (b) the seaward terminus of a lateral jurisdictional boundary agreed to by contiguous states, extending from the land boundary out to the median line in a gulf, lake, or sea; or (c) the lateral jurisdictional boundary between adjacent states, for specific purposes, e. g., from the coastal terminus of a land boundary out to, or toward, the edge of the "continental shelf."

The only practicable and unambiguous definition of the "median line" (applicable in all cases) is "the line every point of which is equidistant from the nearest point or points on opposite shores" of the river, lake, gulf

29 Especially the rule for small "bays" using a graphic method, with one-fourth of the distance between salient points ("headlands") as the radius of arcs for "envelopes" and comparing the area with that of the semicircle of the same radius (Fig. 5, this Journal, Vol. 24 (1930), p. 547).

FIG. 2. Outer limit of inland waters

(A Possible Solution of a Special Base Line Problem)

The first step in delimitation is to lay down the seaward limit of the territorial sea, comprising the envelope of 3-mile arcs passing through such points as B, G, H, J, O, and P. Then in order to supplement the intricate shoreline pattern of mainland and islands by a simpler outer limit of inland waters, and at the same time allow a belt of territorial sea which is everywhere a minimum of 3 miles, it is necessary to describe a series of reverse 3-mile arcs concave toward the land, centered at the points of intersection of the arcs in the "envelope" limiting the territorial sea, from points G, H, J, etc. These arcs will never traverse land, but they will always be tangent to mainland or adjacent islets.

A problem will be seen to arise where outlying islets near M and N determine the territorial sea limit at O, P, etc. An anomalous large area of "inland waters" would result if the reverse arcs were swung from O and P. For inland waters, therefore, seaward arcs from S, T, U, etc., on the larger islands and immediately adjacent islets are described, through Q, R, etc. Then reverse arcs tangent to S, T, etc., would constitute part of the outer limit of the inland waters.

or strait.30 The construction of such a line is shown in Figure 3. An infinite number of points may be found, using a pair of dividers, each of which is equidistant from the nearest points on the left and right banks or shores, as

30 When Col. Lawrence Martin was engaged in the study of the Michigan-Wisconsin boundary question he requested the writer to make a strict delimitation of the median line in Lake Michigan. The technique then developed was made use of, the writer is informed, by the Supreme Court in preparing its decree of March 16, 1936 (297 U. S. 547-52), which corrected the boundary description in the Green Bay section as given in its decree of Nov. 22, 1926 (272 U. S. 398). That study led to the writer's article "Problems of Water Boundary Definition" in the Geographical Review, Vol. 27 (1937), pp. 445-456, which is reproduced (with minor revisions), with permission, in the author's International Boundaries, as Chapter X, "Water Boundaries." See pp. 178-185 in the latter for the elimination of unworkable concepts, with illustrations of certain impracticable verbal and "landsman's viewpoint" concepts, and maps showing strict median lines in Lakes Erie and Michigan.

This illustration is devised especially to present the problems and techniques of laying down a median line in lakes, gulfs, etc., and in particular how to deal with islands. The opposing coasts in this illustration are taken from different parts of the world, and are slightly modified for the present purpose.

(A) The Median Line, the construction of which is here shown, is the line every point of which is equidistant from the nearest point or points on opposite shores. Each of the turning points (found by trial and error with a pair of dividers), such as A, B, C, and D, is equidistant from two or more points on the same shore as well as from one or more points on the opposite shore, e. g., D from L4, Rs, and R4.

(B) The means recommended for determining whether an island is to be regarded as if it were part of the mainland and thus used as part of the base line in laying down the median line-or, on the other hand, whether it is to be disregarded-is here illustrated. First draw that pair of parallel lines tangent to opposite ends or sides of the island which encloses the least area of water between island and mainland, as here shown for "Gross I." (shaded in illustration). If the land area exceeds the water area behind it, the island is used as part of the base line (as here); otherwise it is ignored.

(C) This diagram illustrates an island separated from mainland by a relatively large area of very shallow water-the low-water shoreline not ordinarily being shown on hydrographic charts. The low-water shoreline must be ascertained, and here the area exposed at low tide is shaded. Unless the "island" proves to be part of a peninsula at low tide (as here), the method recommended under (B) would be applied.

indicated by the points L1, L2, R2, etc. The median line constitutes a series of straight lines, each turning point being equidistant from two or more points on the same shore, as well as from one or more points on the opposite shore.

Islands in a lake, gulf or bay may complicate the determination of the base line employed in laying down the median line. Because islands, large and small, are found both near and far out from coasts, in water bodies of all sizes and shapes, it seems uncontrovertible that the median line should, as a general rule, be derived as nearly as proves feasible only from the mainland coast. Obviously, some islands must be treated as if they were part of the mainland. The size of the island, however, cannot in itself serve as a criterion, as it must be considered in relation to its shape, orientation and distance from the mainland. The most reasonable and workable rule is believed to be to draw that pair of parallel lines tangent to opposite ends or sides of the island which encloses the least area

of water between island and mainland, as illustrated for "Gross Island" in Figure 3 (B). Then, if the land area of the island (properly planimetered from the low-tide shoreline) exceeds the water area bounded by the parallel lines, the island and mainland, the island should be reckoned as if part of the mainland base line, in laying down the median line-as is true in the case illustrated. The same technique may be employed with reference to a second island adjacent to an island thus found to be regarded as if mainland-as is also illustrated in Figure 3(B), but its parallel lines must be drawn independently.

When a median line passes very near islands in the middle of a lake or gulf (or even traverses some islands), if any island be found to be "on the wrong side of the median line boundary" (that is, if an island of clearly established sovereignty is in the waters of another state), the alternatives appear to be: (1) Agree to shift the jurisdictional line from the exact median line, to accommodate the island in question; or (2) Agree that the state which has sovereignty over the island shall exercise jurisdiction over it (presumably including its normal belt of territorial sea) without regard to the median line.

The case of an island separated from the mainland by a relatively large area of water which is known to be very shallow (as represented by the high-water shoreline employed as the chart datum) is illustrated in Figure 3 (C). In such instances it will be necessary to determine independently how much of the intervening water area is actually uncovered at mean low-tide, and thus to discover whether the "island" is really a peninsula for base-line purposes, or whether the water area intercepted between the low-tide base lines of both island and mainland and parallel lines constructed as in Figure 3(B) is less or greater than the area of the island area within its low-tide line.

5. Lateral Boundaries through the Territorial Sea, from Land to High Sea

The boundary between two coastal states should terminate, not on the shore but at the point where their respective territorial waters meet the high seas. Principles and techniques which are adequate for all such situations, we believe, are provided in the writer's article "Problems of Water Boundary Definition" in International Boundaries (cited above, footnote 30).

Where there are no islands or exceptionally irregular coastline, the most reasonable boundary is a single straight line from the low-tide terminus of the land boundary to the point of intersection of the envelopes of T-mile arcs drawn from all points on the shores of the two countries-in each instance swinging the arcs shoreward from the land boundary terminus, as if the contiguous state were a water area. Such a line will usually be more than T-miles long, unless the land boundary terminates at a salient point.3

31

Where there are several islands, the most reasonable boundary is a line beginning at the land terminus, usually drawn first to the points of intersection of envelopes of T-mile arcs (as defined above), and continued by median-line techniques between the islands of different sovereignty, and ending at the high seas at the point of intersection of T-mile arcs from the outermost islands.32

An international water boundary defined in accordance with the principles set forth above is found in the Treaty of Peace with Italy, signed at Paris, Feb. 10, 1947, Art. 22, par. (iv):

"(iv) Thence the line follows the main improved channel of the Quieto to its mouth, passing through Porto del Quieto to the high seas by following a line placed equidistant from the coastlines of the Free Territory of Trieste and Yugoslavia."

31 See the writer's International Boundaries, p. 188, Fig. 25, with its explanatory text. 82 See ibid., p. 190, Fig. 26 and its explanatory text. That illustration is based on the problem presented between Panama and the Canal Zone at the Pacific end. The salient points on the mainland and on the islands are identical with those on an accurate map of the Canal Zone and Panama, although the coasts and islands were modified elsewhere, and the illustration was rotated to provide a more convenient position for the legend. But the geometrical line A-B-C (etc.)-K is identical with the writer's conception of a proper boundary in these waters because of the identity of the salient points. The boundary problem in this area was studied because of the claim arising from the collision of the S. S. David (Panamanian) and the S. S. Yorba Linda (U. S. A.), May 11, 1923. The decision of the U. S.-Panama General Claims Commission stated: 66* * * While the treaties undoubtedly fix the boundary between Panamanian territorial waters and the territorial waters of the Canal Zone, it is clear that they do not purport to fix the seaward limit of the territorial waters of the Canal Zone. That is left to the rules of international law" (italics added). See U. S. Dept. of State, Arbitration Series No. 6 (1934), pp. 765-820; also this JOURNAL, Vol. 28 (1934), p. 596; and Hudson, Cases on International Law (2nd ed.), p. 624.