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Show Record July 30, 1929, the gage showed a rise of 4 feet in 25 minutes. This rise was caused by a food from Gypsum Greek, a small tributary entering the river a quarter of a mile above the gage. During this period the quantity of suspended matter increased from 5.5 percent to 8.8 percent. The water during the flood was very red, but the color had disappeared two hours after the peak stage was recorded. 3824 On August 1st, 1929, the gage showed a rise of 1.2 feet in two hours. In that period the quantity of suspended matter increased from 8 percent to 15 percent. On August 12, 1929, the gage showed a rise of 18.2 feet in 20 hours. The maximum during this period being 10.3 feet in 5 hours. The suspended matter during the period increased from 4.4 percent to 8.9 percent. On September 20 and 21, 1929, the gage showed a rise of 6.8 feet in two and a half hours. The quantity of suspended matter increased from .44 percent on the morning of the 20th to 40.3 percent on the morning of the 21st. The percentages which I refer to are by weight, not by volume. 3826 From July 27 to August 5, 1929, a period of rather high water, the total lowd carried by the river was 28,800,000 tons, average percentage of 8.9. On August 12, the period of highest water, a total load of 8,8000,000 tons for the 24 hours. On September 21, a period of less water, but at the same period of 40 percent of silt. I had a total load of 20,000,000 tons. That 3827 is based on the calculation of two sets of samples for that day. I made some observations as to the process referred to as scour and fill. I have charts which show graphically a few of those changes. The charts are based on soundings made from the cable at the period that I took silt out. This chart, Exhibit 495, is based on soundings taken at 9 different points on a cross section of the river at the cable. On September 10, I had a point, say, 4 feet above zero on the gage, but back on August 15, that same |