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below the crest on August 9, and remained below until October 29, reaching a maximum of 10.45 feet below on October 3. Thus during the year 1899 the water was below the crest of the dam one hundred and ninety-one days, during seventy of which the lake level was more than 10 feet below the crest, and during one hundred and sixty-seven it was more than 5 feet below. The evidence was abundant and unmistakable that the flow was not sufficient to carry the city water supply, the street lighting, the street-car systems, and the motors used in the city. Early in 1899 measurements were made at the head of the lake, at Marble Falls, at the forebay, at the tailrace, and at the station below the railroad bridge. These measurements showed conclusively that the minimum flow was less than 200 second-feet. One second- foot, with an assumed effective head of 57.5 feet and a machinery efficiency of 80 per cent, would develop 5.227 horsepower, showing that an average minimum flow of 192 second-feet would be required to produce 1,000 horsepower, not taking into account evaporation and the leaks through the head-gate masonry ("spring"), which would increase the amount. Again, when the lake level fell more water would be required to develop the same power. When the level was 10 feet below the top, 1 second-foot would develop only 4.3 horsepower; and it is highly probable that the efficiency of the machinery was not as high as 80 per cent.

The result was that the enterprise proved disappointing to a large proportion of the citizens. It is true that it had long been before the people, in an indefinite way, but there was not sufficient data at hand to make the results certain. The watershed and rainfall were rather accurately ascertained; but the keystone of the whole project, the biggest and controlling factor, the very life blood of the system, namely, the minimum flow of the river, was overestimated. The feasibility of the enterprise had been demonstrated more than ten years before, and during the interval accurate and reliable data could have been obtained and the minimum flow ascertained with accuracy. Gage heights, rating tables, and flow curves could have been obtained for one-tenth of one per cent of the outlay.

It was found that the minimum flow could be relied upon to furnish water and lights for the citizens and very little more. It was of great value to the city, from a sanitary point of view, that there was during all these years a private water company, whose plant was operated by steam, supplying water and lights to the citizens.

The history of this dam is unique in one respect, and that is in the number of engineers connected with it. Early in 1892 Mr. Joseph P. Frizell resigned, it is asserted, by reason of the fact that he was hampered in his work by the city authorities. Other engineers resigned for similar causes, and at one time a contractor in charge was ordered to follow the instructions of a city official who was not an engineer. This peculiar method of conducting a great public work called forth severe criticisms from engineering journals.