464 PUGET SOUND AND OKONAGAN. 



through. The walls of the Coulee consist of basaltic cliffs, similar 

 to those of the Palisades of the Hudson, seven hundred and ninety- 

 eight feet high ; and where it was crossed by the party it was three 

 miles wide, but a few miles farther to the south, it narrowed to two 

 miles. Its direction was nearly north and south, for a distance of at 

 least fifteen miles. In places, the cliffs were broken, and appeared as 

 though tributary valleys had been formed, in like manner, with per- 

 pendicular walls, though but of short extent. In the northern portion of 

 it were several granite kiioUs, resembling islands, capped with basalt, 

 and called Isles des Pierres. The bottom of the Coulee is a plain, 

 having some irregularities, but in places, for two miles together, to 

 appearance it was perfectly level. There are in it three lakes : one 

 on the top of the west border, another after descending, and a third 

 between two of the granite islands. The last of these was the largest, 

 being about a mile long, but is not more than three hundred feet broad : 

 these lakes have no visible outlets. Although the soil abounded in 

 the same saline efflorescence that had been remarked on the high 

 prairie, yet the lakes were found to be fresh, and wild ducks were 

 seen in great numbers. In other spots, the earth was damp and over- 

 grown with a rank grass, of the same kind as that growing on the 

 prairie. Next to this, the wormwood predominated. 



In the level places the earth was much cracked : incrustations were 

 abundant, which, sparkling brilliantly in the sun, gave the plain 

 somewhat the appearance of being covered with water. Specimens 

 of these were procured, the analysis of which will be found in the 

 Geological Report. 



The granite islands, above spoken of, were found to be seven 

 hundred and fourteen feet high. Mr. Johnson named the southern 

 one the Ram's Head. Dr. Pickering, who visited the north part, 

 found no regularity of structui'e. All were satisfied, after leaving 

 the Coulee, that it had been the seat of a lake, in the northern 

 branch of which, some convulsion liad caused a breach, through 

 which it had discharged itself into the Columbia. If the Columbia 

 had ever flowed through this chamiel, it must have worn the rocks, 

 but they exhibit no signs of any such abrasion; and yet it seems 

 remarkable, that the Coulee had extended from one point of the river 

 to another, and, with the exception of its breadth, forming very much 

 the same kind of trench as the Columbia would leave, if it forsook 

 its present channel. 



From the observations subsequently made at the lower end of the 



