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Show 3218 Dent- D 1244 A As I personally observed it, I took a tumbler we had emptied in the course of our consumption of rations, and took samples of water at a number of points. I found that there was a very considerable deposit of sand of a character that would settle through still water at the rate of one foot per minute, or greater. Comparing that with my experience on the Lower Mississippi river, the charge of sand was extremely heavy. I might say that sand of that size is approximately one- four- hundredth of an inch in diameter, or greater. In addition to the sand which settled at this rate of a foot or more, and which in my experience is ordinarily quite troublesome, there was apparently about an equal quantity of sand that settled at the rate of about one- fourth that speed. Now, this solid settling sand could be quite readily carried in suspension, and would not make as much trouble as the coarser sand first mentioned. As to the quantity of this sand, the only indications I have are official records of the lower Colorado river in the vicinity of Yuma, if those are desired. Q What about the gradient of this river? A The gradient of the river, as shown by the maps, is over one foot per mile, with steeper sections that considerably exceed one foot per mile. |