Sketch of the Life of Mr. David Douglas. 271 



" I have arranged my barometer every way to please me, but I 

 wish you had been with me to have lent me a hand, for I had 

 some trouble boiling the mercury in the tube. Fortunately I can 

 find only '004 of an inch of index error, from the comparison I 

 made with it and my others at Greenwich. I could have done no 

 more, had I been in Dolland's shop. I shall give you the altitude 

 of the mountains in my next, which I hope will be numerous, on 

 the Willamette Ridge." 



In fulfillment of this promise he wrote me again on the 29th 

 November from Fort George (Astoria). 



" By Mr. Ogden I was favored with your kind letter, relating 

 to the crop on the Wallawalla River, together with other good 

 things it contained. I hold myself greatly in your debt, and sin- 

 cerely thank you for the same. I had an extensive journey in the 

 Willamette with Mr. McLeod, and benefited myself, besides being 

 greatly gratified by it. The valley is by no means of that extent 

 generally ascribed to it; where we apply the test of measurement 

 it indeed falls far short. The basin of the Multnamah, that is the 

 country bounded on the east by the woody ridge of mountains 

 that skirt the coast and generally keep parallel to it, and that 

 ridge of the cascades which forms the platform of Mount 

 Hood, (and of the culminant points of land to the south, which 

 preserve a nearly south-west direction until they dip into the sea,) 

 the termination of which is Cape Orford, is from the Columbia 

 Valley to the most remote high lands that divide it from the 

 Umptqua, only 127 miles, the breadth being about 70 from east 

 to west, forming nearly a triangle. The soil is not so well calcu- 

 lative for tillage as represented. It is parched in summer, and 

 its herbage destroyed by crickets. In winter it is deluged by rain, 

 all its depressed parts, called plains, being covered with water. 

 The highest land on which I was on that Willamette Ridge is 

 1043 feet elevated above the apparent base. This is barometrical 

 but observe I should not adopt it, only as a very close aj^proxima- 

 tion to its real height, for want of simultaneous observation at the 

 base, when at the peak myself. I was obliged to take the mean of 

 a series of observations before starting, and after my return, as 

 true for the lower station. With all these disadvantages, I am 

 truly gratified to state to you that my geometrical measurement 

 was 1013 feet. All and more than ordinary care was taken as to 

 the base line ; and to do away with errors of eccentricity of the 

 instrument and the like, generally found in the most perfect 



