PARRY — GREAT CANON OF THE COLORADO. 503 



and probably comprised long stretches of still water, it would 

 not be safe to allow a distance of more than thirty miles per 

 day, or three hundred miles for this interval. Thus, the whole 

 distance travelled would amount to five hundred and fifty 

 miles, or something over five hundred miles from Grand River 

 junction to head of steamboat navigation at Callville. 



4th. The absence of any distinct cataract, or perpendicular 

 falls, would seem to warrant the conclusion that in time of 

 high water, by proper appliances in the way of boats, good, 

 resolute oarsmen, and provisions secured in water-proof bags, 

 the same passage might be safely made, and the actual course 

 of the river with its peculiar geological features properly de- 

 termined. 



5th. The construction of bridges by a single span would 

 be rendered difficult of execution on account of the usual flar- 

 ing shape of the upper summits; possibly, however, points 

 might be found where the high mesas come near together. 



6th. The estimated average elevation of the Canon at 3,000 

 feet, is less than that given on the authority of Ives and New- 

 berry, but may be nearer the actual truth, as the result of 

 more continuous observation. 



7th. The width of the river at its narrowest points was es- 

 timated at 100 feet, and the line of high- water-mark thirty 

 to forty feet above the average stage in August. 



8th. The long continued uniformity of the geological forma- 

 tion, termed "white sandstone" (probably Cretaceous), is 

 remarkable, but under this term may have been comprised 

 some of the lower stratified formations. The contrast, on 

 reaching the dark igneous rocks, was so marked that it could 

 not fail to be noticed. 



9th. Any prospect for useful navigation up or down this 

 canon during the season of high water, or transportation of 

 lumber from the upper pine regions of Green or Grand Riv- 

 ers, could not be regarded as feasible, considering the long 

 distance and the inaccessible character of the river margin 

 for the greater part of its course. 



10th. No other satisfactory method of exploration, except 

 along the course of the river, could be adopted to determine 

 its actual course, and peculiar natural features, and James 

 White, as the pioneer of this enterprise, will probably retain 

 the honor of being the only man who has traversed, through 

 its whole course, the Great Canon of the Colorado, and lived 

 to recount his observations on this perilous voyage. 



