ROCKY MOUNTAIN MEDICAL ASSOCIATION. 4I 
these ruins has awakened unusual interest in the study 
of the condition and habits of the prehistoric races of 
North America. The cave-houses or cHff-dwelhngs 
are found in or along the deep canons and located 
in ledges of the rocks, at almost inaccessible heights 
varying from a few hundred to a thousand feet 
above the bed of the river.* Some are in a good 
state of preservation, but for the most part they are in 
ruins. All of them, however, show skill as well as 
great labor and perseverance on the part of those who 
constructed them. 
The cliff-houses partake somewhat of the character- 
istics of cave habitations, but they are a vast improve- 
ment upon them, and show a decided advancement in 
resources and knowledge. I am inclined to think that 
these semi-caves and cliff ruins show the earliest 
divisions of the house into apartments to be found 
in America. Major Powell, however, considers them 
of more recent construction than the Pueblo adobe 
ruins existing in the same region. The pottery and 
other implements so far found in and about them sug- 
gest that they have probably been inhabited by an in- 
trusive race, since their builders ceased to occupy these 
structures. It is very probable that long antedating the 
building of these cliff-houses, and even the existence 
These structures are of stone, requiring but a front wall and such 
partitions as they chose to make. A peculiarity is that nearly all 
have a circular room or apartment, and seldom with windows. Occa- 
sionally round stone towers are found built on high promontories and 
isolated peaks, resembling the round ta,wers or Cuthite remains so 
numerously found in Ireland. Towers of a similar character are 
known to exist in Eastern Europe and Asia, in Peru and other parts 
of the world, and possibly served as temples to a very early civiliza- 
tion. 
