VALUE OF FIORDS AS PORTS l8i 



modified by the ice stream which recently occupied their 

 beds. 



In their characteristic development in high latitudes fiords 

 offer singularly good harbors for ships. The main channels, 

 however, are often too deep to afford safe anchorage ground, 

 but in the shallower branches of these bays it is generally 

 possible to find perfectly landlocked havens exactly suited to 

 all the needs of shipping. Inlets of this description are, as 

 a rule, admirably protected from the action of those agents 

 which tend to destroy many other harbors. The streams 

 that enter them rarely convey any considerable quantities 

 of sediment which micrht effect a shallowinir of the basin. 

 The waters of these rivers are unmincrled with sediments, 

 for the reason that they flow from drift-covered countries 

 which send little muddy matter, and, moreover, the streams 

 themselves commonly pass through lake basins which afford 

 settling pools for such sediments as the flood waters may 

 bear. The fringe of islands which commonly lies off the 

 shores of a horded district often affords shelter of a valua- 

 able sort for craft which are undertaking coastwise voyages. 

 Thus for the greater part of the distance from Portland to 

 Eastport, Maine, it is possible for small craft to journey 

 without being exposed to the ocean waves, within the pas- 

 sages between the islands and the mainland. The protec- 

 tion afforded by such island fringes is even more continuous 

 on the western coast of North America, where the barrier 

 of islands extends from Puget Sound northward for a dis- 

 tance of more than seven hundred miles, with but slight 

 breaks which expose a vessel to the open sea. 



The effect of a well-developed fiord structure is greatly 

 to increase the length of a shore-line. The measure of this 



