32 
THE BOTANY OF THE ROUTE. 
mollusca are also rare, being confined almost exclusively to the lakes, marshes, and sloughs 
near the river, which become warmer in summer. 
The Columbia continues fresh so near its mouth that I have found the water drinkable even 
at high tide, and in August, just within Cape Disappointment, less than a mile from the 
breakers outside the bar. 
To this fact is attributable the scarcity of such animals as usually inhabit estuaries. Though 
I visited the place at all seasons I never found on the shores of Baker’s bay but two species of 
mollusca, while in the bay, only a mile or two north of it, are more than twenty. But several 
species are known to inhabit the deep water about the bar of the Columbia, where they were 
dredged up by the Exploring Expedition. It is probable that the water is much salter at that 
depth than near the surface. 
Aquatic mammalia, such as the beaver, muskrat, otter, and seal, abound in the fresh waters; 
and one seems to be peculiar to the Territory, the water shrew, (Neosorex navigator,) caught 
while swimming a foot below the surface of one of the lakes at the head of the Yakima river, 
and at least 2,500 feet above the ocean. 
SALT WATERS OF THE TERRITORY. 
The salt waters of the Territory constitute a botanical and zoological region, equal in 
importance to the others described, and, in their great variety of animal life, far surpass the 
corresponding portions of the Atlantic coast. A short description of the peculiarities in the 
conformation of the shores will, in some degree, account for this fact. Commencing with the 
northwest sounds, we find there a large body of water from twenty to sixty fathoms deep, with 
shores almost everywhere bold and hard, so that the largest ships can literally tie fast to the 
trees along shore in many portions where they cannot readily anchor on account of the depth. 
This great body of water is nearly as salt as the ocean itself, and is renewed twice in each day 
by tides, which range between the limits of eighteen feet, each alternate tide being less than 
the preceding, until it is reduced to a rise or fall of less than a foot, when it begins to 
increase again, the other series decreasing in its turn. By this arrangement it happens that 
the extreme low tides occur about once in every fortnight. 
The high mountains, and generally steep cliffs on each side, completely protect the sounds 
from storms, so that calms are almost constant in their inner labyrinths, and they are thus as 
admirably fitted for the production of animal life as the most carefully constructed aquarium. 
In very short visits and hasty voyages on the sounds I had little opportunity for collecting, and 
obtained, I believe, nothing new. But the great number of animals obtained by others, and 
most of which exist in abundance, show its richness in zoology, while it may be safely estimated 
that a third of its inhabitants are yet unknown to science. 
A longer residence at Shoalwater bay allows me to speak of it more particularly. It is 
twenty-five miles long and from three to seven wide, thus including an area of more than a 
hundred square miles. Of this large surface two-thirds may be said to become bare at ordinary 
low tide, and probably more than three-quarters at the lowest semi-monthly ebbs, of which 
those of May and June are even lower than the others, though all less in their extremes than 
those of the sounds. 
The least depth of water on the bar is, by the Coast Survey charts, three and a quarter 
fathoms, which increases just within it to seventeen fathoms, and varies in the channels from 
this depth to three fathoms at the mouths of the larger rivers. There are five rivers emptying 
into the bay, which bring down a large amount of fresh water, and six large creeks, which, 
