964° General Notes. [ November, 
the area in question, revealed other and more interesting facts 
concerning the growth of the lodes in this restricted area. It 
soon became evident that the extremely peculiar topography of 
the country at the head of Red creek, in Ouray county, could have 
been produced only by the accumulative action of numerous enor- 
mous geysers, far more effective than those to-day at work in the 
Yellowstone Park, though occupying, perhaps, a less extensive 
basin. Probably, however, not a little of the area over which the 
hot spring deposits can be traced, may have been the seat of im- 
portant geysers. In fact, there are reasons for making this state- 
ment more definite, but it will be best to confine ourselves to 
what can be clearly described in a few words, without considera- 
tion of nice structural details. 
The upper valley of Red creek is thickly studded with mounds 
of varying size, but not widely different in form. All these are 
more or less closely connected with the present (or compara- 
tively recent) local drainage, which is also bounded at irregular 
intervals by dry pits and pools of cold water quite similar to the 
bowls of existing hot springs in other localities. The remarkable 
characteristics of this basin are the number and the magnitude of 
the mounds and the total absence of active thermal springs, not- 
withstanding the existence of such in localities not far distant, as 
át Ouray. The altitude of the district is from about 9500 feet to 
12,000 feet, whereas few, if any, of the present hot water bowls 
are known above 6500 feet, hereabouts. 
The cañon of Red creek is undoubtedly not one wholly of 
aqueous erosion, but the drainage has been induced in part by 
seismic action, modified in an interesting manner by glacial scor- 
ings and subsequent diluvial deposition. The Red Mountain 
geyser area, as we may designate this tract, is now topograph- 
ically restricted, as here indicated, almost wholly to the upper 
portion of this interesting cañon, but it may be really separated 
into three well-marked basins, which formerly fed as many sepa- 
rate affluents of the main stream. Two of these are proven to be 
metalliferous, while the third is almost unexplored; though giving 
indications of similar character, but less promising perhaps. f 
The geyser areas do not seem to extend beyond the region © 
maximum intensity of the volcanic action in the rhy olytic 
period, and the ore-bodies all furnish evidence of secondary re- 
actions taking place in the line of a prominent fault-fissure of that 
age. All along this course over a considerable breadth of terri- 
tory, the remains of extinct thermal springs are (recognizably ) 
_ most abundant, but the geyser character is not noticeable far 
_ towards the north or south of Red peak. : f 
The ormations in the vein material, the aggregation id 
-~ the ores into bonanzas (as at the Yankee Girl, Alaska and O 
Lout mines, among others) with the very remarkable distribution 
minerals in the lodes, are but a few of the intensely interesting 
m 
