liEPORT OF CAPTAIN HUMPHREYS TO THE SECRETARY OF WAR, 185G. 29 



Either standard applied to the two routes — the route to Saa Diego by Warner's pass, and 

 that to San Pedro by the San G-orgonio pass — will give about the same total cost for each. If 

 the object is to reach the bay of San Francisco, the route through the San Gorgonio pass is 

 preferable, since, after reaching San Diego through Warner's pass, at a cost equal to that of 

 the route through the San Grorgonio pass to San Pedro, there would remain the distance between 

 San Diego and San Pedro — nearly 100 miles — over which it would be necessary to build the 

 road. 



In obedience to instructions from the War Department, dated May 1, 1855, a party was 

 organized by Lieutenant R. S. Williamson, corps of Topographical Engineers, to examine the 

 country lying between the Sacramento and Columbia rivers, with a view to ascertain the practi- 

 cability of connecting their valleys by a railroad. 



The first 200 miles of the route — from Benicia to Fort Reading, in the Sacramento valley — 

 pass through a settled country. The average grade would not exceed five feet, and bridges 

 would form the only expensive item in the construction of a railroad. Timber and water are 

 abundant. 



From Fort Reading, two routes to the Columbia river were examined — one east of the Cascade 

 range, and the other between it and the Coast range. The former crosses the western branch 

 of the Sierra Nevada by Noble's pass — a difficult location for a railroad, as there is an ascent, 

 in a distance of 40 miles, of about 6,000 feet. A better line for crossing this range can be had 

 by ascending Pit river along the route surveyed by Lieutenant Beckwith. A careful examina- 

 tion of the two cailons of this river developed results less favorable than those obtained by 

 Lieutenant Beckwith, but nevertheless demonstrated the practicability of constructing a rail- 

 road near them. 



The route beyond the upper caiion of this river lies for about 250 miles over a plateau — 

 mostly sterile, though well supplied with water — elevated between 4,000 and 5,000 feet above 

 the sea. This plateau extends from the western chain of the Sierra Nevada, northward, beyond 

 the Columbia, gradually declining towards that river from the head of the Des Chutes valley. 



Where timber is wanting in the immediate vicinity of the route, which rarely occurs, the 

 mountains bordering it on the west will furnish an abundant supply. 



For nearly the whole distance the average grade will be less than 25 feet, though in a few 

 instances it rises to 100 feet, per mile. Difficult work will be found near Upper Klamath lake, 

 and between it and Klamath marsh, where some heavy cutting and filling will be requisite. 

 At the latter place it will be necessary to follow the caiion of Klamath river for about six miles. 

 Near the head of the Des Chutes valley the party divided. Lieutenant Williamson, after a 

 careful examination of the Cascade range in this vicinity, crossed it near Diamond Peak by a 

 pass through which a wagon road has been made. Both the ascending and descending grades 

 ■were found to be very abrupt. By the road, the ascending grades were for 2.5 miles 231 feet ; 

 for 4.7 miles 72 feet, and for 2 miles 42 feet per mile. The descending grades were for 5 miles 

 23 feet ; for 3.7 miles 512 feet, and for 2.5 miles 311 feet per mile. Below this point they were 

 all less than 125 feet per mile, and they continued to diminish rapidly. The above grades 

 might be reduced by a side location to an ascending grade of 150 feet per mile for 7 miles, and 

 a descending grade of 180 feet per mile for 16 miles, and perhaps even still further. There 

 will be great difficulty in cutting through the dense forest. The summit of the pass is 5,600 

 feet above the sea. 



After crossing the Cascade mountains, the Willamette valley was followed for 150 mile§ to 



