DENVER & RIO GRANDE WESTERN ROUTE, 87 
rocks have been traced eastward to a point near the fault at the 
edge of the granite. As the lava rises steadily toward the east the 
volcanic vent from which it came was probably near the fault and 
on high ground, thence it flowed westward down the slope to the 
river, which was then farther west and somewhat lower than it is 
to-day. 
The volcanic matter doubtless partly filled the old valley of the 
Arkansas, and then came a great wash of gravel and boulders from 
the mountains, which must have filled the valley to a depth of sev- 
eral hundred feet. No one yet knows what caused this great deposit 
of gravel, but it has been assumed to have some connection with the 
formation of great glaciers in the neighboring mountains, This in- 
flux of foreign material dammed the river and forced it over to the 
east side of its valley, entirely out of its former position. At present 
the river is cutting away the gravel and lava, but it has not yet cut 
down to its former level. Remnants of the gravel filling may be 
seen in the extensive terraces opposite Howard, as shown in Plate 
XUIT. 
At Howard a branch railroad turns to the left, crosses the river, 
and disappears in the hills in the distance. This line runs to a stone 
quarry at the station of Calcite, where limestone is being quarried 
on a large scale by the Colorado Fuel & Iron Co. for use as flux in 
its large blast furnaces at Pueblo. Howard is a 
Howard. small village, but the well-cultivated farms across 
Elevation 6,718 feet. the river indicate a prosperous community. The 
en oer land on both sides of the river is irrigated and 
"yields abundant crops of alfalfa and the more hardy 
grains. Near the station there are kilns in which charcoal was for- 
merly made. (See Pl. XIV, B, p. 30.) These kilns are the only 
traces that remain of what was once a large industry in these moun- 
tains. The native timber was used in making charcoal, which was in 
great demand by smelters in almost every mining town. The con- 
centration of the smelting industry into the hands of large corpora- 
tions and the consequent abandonment of most of the small plants, 
together with the increased production of coke in the coal fields near 
, killed the charcoal industry. Although the decay of this indus- 
try temporarily deprived many persons of the means of making a 
livelihood, it was a blessing to the region as a whole, for the manu- 
facture of charcoal is a wasteful process and one that has consumed 
Pee valuable timber that might have been reserved for a more use- 
ul pu : 
A little beyond Howard the railroad turns more toward the west 
and crosses the bedded rocks, which show to good advantage. In 
