MODES OF THE ACQUISITION AND LOSS OF TERRITORY
169. There are five modes by which a State may acquire a legal title to territory.
Accretion. -- (1) By Accretion, which is, comparatively speaking, of slight importance. It consists in the increase or enlargement of the land territory of a State mainly1 through the action of its rivers or the ocean. These formations are usually caused by gradual alluvial deposits at the mouths of rivers (deltas) and on the seacoast. New islands formed in rivers, lakes, or within the maritime belt belong to the neighboring State or States. In the latter case, the marine league is measured from the shores of such islands.2
170. Prescription. -- (II) By Prescription, which has been well defined as "the acquisition of sovereignty over a territory through continuous and undisturbed exercise of sovereignty over it during such a period as is necessary to create under the influence of historical development the general conviction that the present condition of things is in conformity with international order."3
It has been denied4 that usucapion or acquisitive prescription can furnish a good title to territory, but the majority of publicists admit that long-continuous and____________________
The rules governing accretion are derived from Roman Law. See Justinian,
2 Institutes, I, 20-24; 42 Digest, I, 7, 29, 65; and Grotius, II, c. 8, §§ 8-16.