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Show Record proper method for making these calculations. At Cisco for that same year the load was 25,000,000 tons. On the San Juan River, for samples taken at the Goodridge Gaging Station over the period from May 1st to September 1st, the load computed for yearly load, figures out 60,200,000 tons. 3806 At Lees Ferry for the same period the load was 131,000,000 tons. That is about the same as the total of the three stations indicated. It may be 4,000,000 or 5,000,000 tons less, but approxi-mately it is the same load as comes in from the three upper stations. There is no particular reason why it should be the same for that given period because the load, as it passes Greenriver does not go instantaneously past the junction of the Green and the Colorado, or past Lees Ferry Station. I mean by that, that the 50,000,000 tons that passed Greenriver in the year ending September 30, 1929, would not neces- 3807 sarily have reached Lees Ferry during that year. Of that load of 131,000,000 tons that reached Lees Ferry, 50,000,000 tons may have come from Greenriver, but may not have come during that particular year. I have shown that between our stations at Bright Angel and Topock, the load for any given period is quite different. During the fall the Topock Station carries a larger load than the Bright Angel Station. The Bright Angel Station is about 250 miles above Topock, but during the spring floods, the larger load is carried at the Bright Angel Station. Of course volume of water and velocity of water must be considered. That is, 50,000,000 tons at Greenriver with a certain amount of water, would have a different effect 3808 than 50,000,000 tons with other amount of water. A showing of 50,000,000 tons in the Mississippi River at a given point would be quite different from a showing of 50,000,000 tons in the Connecticut River at a given point. We figure the percentage by weight carried at these various points. At Greenriver it is .66 and at Cisco .27. The river flow at Greenriver and Cisco are the same. So the water at Cisco is much clearer than the water at Greenriver. On the San Juan the percentage |