MAUVAISES TERRES. 197 
benches, towards the spurs of the Rocky Mountains, the traveller looks down into 
an extensive valley, that may be said to constitute a world of its own, and which 
appears to have been formed, partly by an extensive vertical fault, partly by the 
long-continued influence of the scooping action of denudation. 
The width of this valley may be about thirty miles, and its whole length about 
ninety, as it stretches away westwardly, towards the base of the gloomy and dark 
range of mountains known as the Black Hills.* Its most depressed portion, three 
hundred feet below the general level of the surrounding country, is clothed with 
scanty grasses, and covered by a soil similar to that of the higher ground. 
To the surrounding country, however, the Mauvaises Terres present the most 
striking contrast. From the uniform, monotonous, open prairie, the traveller sud- 
denly descends, one or two hundred feet, into a valley that looks as if it had sunk 
away from the surrounding world; leaving standing, all over it, thousands of abrupt, 
irregular, prismatic, and columnar masses, frequently capped with irregular pyra- 
mids, and stretching up to a height of from one to two hundred feet, or more. 
So thickly are these natural towers studded over the surface of this extra- 
ordinary region, that the traveller threads his way through deep, confined, labyrin- 
thine passages, not unlike the narrow, irregular streets and lanes of some quaint 
old town of the European Continent. Viewed in the distance, indeed, these rocky 
piles, in their endless succession, assume the appearance of massive, artificial struc- 
tures, decked out with all the accessories of buttress and turret, arched doorway 
and clustered shaft, pinnacle, and finial, and tapering spire. 
One might almost imagine oneself approaching some magnificent city of the dead, 
where the labour and the genius of forgotten nations had left behind them a multi- 
tude of monuments of art and skill. : 
On descending from the heights, however, and proceeding to thread this vast 
labyrinth, and inspect, in detail, its deep, intricate recesses, the realities of the scene 
soon dissipate the delusions of the distance. The castellated forms which fancy 
had conjured up have vanished ; and around one, on every side, is bleak and barren 
desolation. 
Then, too, if the exploration be made in midsummer, the scorching rays of the 
sun, pouring down in the hundred defiles that conduct the wayfarer through this 
pathless waste, are reflected back from the white or ash-coloured walls that rise 
around, unmitigated by a breath of air, or the shelter of a solitary shrub. 
The drooping spirits of the scorched geologist are not permitted, however, to flag. 
The fossil treasures of the way, well repay its sultriness and fatigue. At every 
step, objects of the highest interest present themselves. Embedded in the debris, 
lie strewn, in the greatest profusion, organic relics of extinct animals. All speak 
of a vast fresh-water deposit of the early Tertiary Period, and disclose the former 
existence of most remarkable races, that roamed about in bygone ages high up in 
the Valley of the Missouri, towards the sources of its western tributaries; where 
now pastures the big-horned Ovis montana, the shaggy buffalo or American bison, 
and the elegant and slenderly-constructed antelope. 
* See small map of Bad Lands. 
