528 APPENDIX. 



A theodolite, chain, dredge, the eprouvette, and a howitzer, are fur- 

 nished you for measurements of base, &c. 



You will supply yourself with the signals required for surveying 

 service, and see that each of your officers is furnished with the signal- 

 book and answering pendants. 



Referring you to my General Order of May 1st, and wishing you 

 success in the execution of these instructions, 



I am, &c, 



Charles Wilkes, 

 Commanding Exploring Expedition. 

 Lieutenant A. L. Case, 



U. S. Ship Vincennes. 



XII. 



U. S. Ship Vincennes, 



Nisqually Harbour, May 13th, 1841. 



Sir, — 



You are entrusted with the charge of the party, consisting of your- 

 self, Mr. Thomas W. Waldron, Dr. Pickering, Mr. Brackenridge, 

 Sergeant Stearns, and Henry Walthrown (ordinary seaman), for the 

 exploration of the district pointed out in the accompanying map. 



You will leave this place on the 17th, and proceed by the route 

 that will lead you across the mountain range north of Mount Rainier, 

 of which it forms a part. Thence you will pursue a route to the 

 northward, keeping to the west of the Columbia river until you reach 

 Fort Okonagan, where you will doubtless obtain much information 

 relative to the country, and proper guides to proceed with. From 

 thence I should desire you to push to the northward, if possible, and 

 your time will permit, making a detour so as to stop at Fort Colville ; 

 thence across the Saptin or Lewis river, and down to Fort Nez 

 Perce, and thence, in a direction to Mount Rainier, to Nisqually, 

 where you "will join me or receive orders to govern your farther 

 movements. 



The route I have pointed out I believe to be feasible, but as the 

 country is little known, it may not be so. My object is to get infor- 

 mation respecting the district I have marked in red, and you will 

 endeavour to get this as accurately as possible, by travelling over as 

 much of its surface as your time will admit of. You are limited to 

 two months' absence, and I am well convinced that much knowledge 

 may be gained of the district pointed out to you, in that time. 



Your inquiries at posts and forts will lead to much information of 

 the country, with its capabilities, productions, climate, soil, &c. 



They will particularly embrace the following, viz.: 



