478 Reviews—Survey of Colorado. 
The Geological series described embraces the Tertiaries of Unita, 
Bridger, Green River, and Wahsatch, comprising beds of coarse 
friable sandstones and conglomerates; the Post-Cretaceous of 
Laramie, containing carbonaceous layers and beds of coal, inter- 
calated with reddish, ferruginous, and yellowish sandstones; the 
Cretaceous beds of Fox Hills, Colorado, and Dakota, containing 
clayey and sandy shales; the Jura-Trias of different coloured sand- 
stones, with calcareous fossiliferous rock; and lastly the Carbon- 
iferous strata, consisting of sandy and calcareous beds, with masses 
and nodules of chert, compact bluish fossiliferous limestone, 
sandstones, sandy limestones, and hard and often quartzitic brick-red 
sandstones. These rest on the Weber quartzite. The sections and 
outline illustrations of these strata are most admirably rendered ; 
and a further series of sketches of the weathered and eroded sand- 
stones forming “monuments,” such as the “‘ Happy Family ” group 
in the White River Canon, are also given. Speaking of the latter, 
Mr. Endlich observes, ‘“‘The most frequent form exhibited is one 
closely imitating ruins of some ancient building or city. Seen by 
the slanting rays of a setting sun, the hills seem fortified, each by a 
castle of enormous dimensions, that throws a long-drawn shadow to 
the eastward. Turrets and battlements are supplied by the skilful 
hand of nature, that teach, by their form, the source whence human 
ingenuity copied them.” 
It is also advanced that, though the canons have been mainly 
carved out by water-action alone, there seem to be indications of 
ice-action in the marking out of their original directions, though the 
softness and friability of the rock materials would prevent any direct 
traces being found now. 
An excellent monograph on the erupted rocks of Colorado, and a 
catalogue of the minerals found in Colorado, add much to the value 
of the volume; but perhaps the most interesting portion is that 
contributed by Mr. William H. Holmes, on the archeology of the 
districts surveyed. They seem even more extensive than those 
previously described, but occupy the same positions as in other parts 
of the Colorado, that is, rock-shelters and caves, situated high up on 
the steep sides of the valleys, and improved by the addition of 
masonry into terraces, walls, and houses. Although the country is, 
generally speaking, dry and barren, and seems: almost incapable of 
supporting a population so extensive, apparently, as that which 
originally occupied it, the streams and springs, near which the 
remains are exclusively found, are bordered by grass-covered bottoms 
and alluvial tracts; and these, if perfectly utilized, would afford a 
considerable area of rich tillable land. 
As a rule, the buildings are of regular form, that is (where the 
ground permits), either in perfect circles or perfect squares; and in 
the larger towers the space between the outer walls is divided by 
heavy partition-walls into a number of apartments, with a circular 
depression or Estufa (or council-house) in the centre. Quantities of 
flint chips, and fragments of pottery, were found in the neighbour- 
hood of the habitations. The fictile fragments are richly marked, 
