DEXVER & RIO GRANDE WESTERN ROUTE. 91 



The railroad ascends this canyon for several miles and tlien climbs 

 the momitain slopes on the west, finding a way, after many turns and 

 loops, over the range through Marshall Pass, which lies just beyond 

 Ouray Peak (oo'ray), as shown in Plate LXIX, B (p. 162). Al- 

 though the line up the Arkansas Valley above Salida was completed 

 as far Leadville in 1880 and the line over Marshall Pass in 1881. the 

 latter was regarded as the main line and was the first to be finished 

 through to Salt Lake City. 



Near milepost 217 a branch line turns to the left to a large silver- 

 lead smelter in which much of the ore of this region is reduced. A 

 description of such a plant and of the process of smelting is given 

 on pages 252-251. A little farther on there is an abandoned mill 

 on the right of the track, one of the characteristic features of a 

 mining country that has seen its best days. The old mine that 

 supplied ore to be crushed and concentrated in this mill may be 

 seen halfway up the moimtain slope on the right. The mill and a 

 single house constitute Belleview, which is merely a siding for 

 trains. A short distance beyond Belleview the railroad crosses the 

 Rainbow Highway, which for some distance beyond this point con- 

 tinues on the right of the track. 



From Salida up to the Continental Divide and for some distance 

 down on the western slope the shape of the mountains has been 

 greatly modified by glaciers. There are no glaciers in these moun- 

 tains now, but long ago, during the great ice age, these ranges, 

 particularly their east sides, were covered by great masses of ice 

 which flowed down toward or into the vallej's at their feet, scouring 

 out here and there basins from the solid rock. As most of the strik- 

 ing scenery in this region is due to the effect of these bodies of mov- 

 ing ice the}' are shown on the accompanying maps as they existed 

 at the time of their greatest development. The effect of high winds, 

 low temperature, and snow on the vegetation at high altitude is 

 also well shown at the summit of the moimtains, as exliibited in 

 Plate XLV, J., which is a view from the automobile road where it 

 crosses the Sawatch Range west of Salida. 



About milepost 220 there are many large boulders, like those at 

 Parkdale, on a low ten-ace near the river. As the railroad ap- 

 proaches the river the boulders may be seen at close range and at 

 higher levels, until they appear on the terrace above tlie one on 

 which the railroad is built. These boulders increase in size north- 

 ward until at a place about a mile from the mouth of Brown Canyon, 

 which is apparenth' the place from which they were swept, there 

 are boulders of great size; one on the left of the track measures 

 24 by 14 by 10 feet. 



