90 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
shore. The dredge brings up gravel, sand, and mud, the texture 
of the sediments being finer as the distance from the land and the 
depth of the water increase. Very little of these land-derived sedi¬ 
ments is found more than one or two hundred miles off shore. All 
this means that, while the land has been dissected and roughened by 
the action of weather and streams, the sea fioor has been smoothed 
over bv lavers of sediment furnished by the wasting lands. 
A rugged land like this can seldom support a large population. 
It is chiefly in the valleys that strips of flat land, suitable for easy 
occupation, can be found; and these are often exposed to the danger 
of floods from the torrential streams which rise suddenly over their 
banks after a heavy rain or thaw. Most of the scanty population is 
ordinarily gathered in villages near the mouths of streams or rivers ; 
the rest live scattered over the lower hills near the shore, crowded 
in the narrow inner valleys, or spread over the smoother and 
more accessible uplands. Movement is difficult, except along the 
valleys. It is not easy to reach the interior country beyond the 
mountains, for the passes are high and rugged, often crossing over 
snowfields and glaciers. In moving parallel to the shore line from 
one valley village to another, the traveller must climb over the 
intervening ridges, where notches determine the place of paths and 
roads. No roads can follow immediately along the bold sea shore, 
for most of the cliffs are washed to their base at every tide. 
Protected harbors are rare on such a coast; the best ones are 
found in slight re-entrants between headlands, or in the mouths of 
the larger rivers. The ridges, cut off by sea cliffs, afford no landing 
place; the boldest of them may be crowned with lighthouses, to 
warn the mariner from the rocky stacks and skerries, remnants 
of the headlands near the shore not yet consumed 
Certain parts of the coast of California may be compared to the 
type here described. The Sierra Santa Lucia, south of Monterey, 
descends boldly to the sea; its slope is hardly inhabited for seventy 
miles. North of San Francisco, a less severe type of form prevails; 
the mountains there are not so bold, and more space is offered for 
settlement near the sea. 
The Mediterranean coast, from Nice past Genoa to Spezia, is a 
famous example of this class, more densely populated than is usual. 
The mountains rise rapidly from the water’s edge. Streams run 
like torrents to their very mouths. Little villages nestle in the 
slight re-entrants of the coast; their boats are poorly sheltered 
by the waves. 
