April 4, 244,333 38° 43° 21h.40m. 0 April 1, .06 .0038 .0020 .15 .0340 .0000 8, .05 .0042 .0032 .16 .0360 .0000 Surface raked about 1 inch deep each week, commencing Jan. 1, 1891. Snow and ice removed from surface January 6, 12, 20, 26, February 9, 16, March 2, 4 and 5. Experiments interrupted by high water in the river January 25, 26, February 27, 28, March 1, 12 to 29, April 14 to 18. Effluent clear and odorless. City water applied 6 times a week to November 12 and afterwards canal water applied 6 times a week. Surface raked about 1 inch deep each week. Effluent clear and odorless. The following table contains a summary of twenty-five microscopical examinations of the effluent : DATE. Microscopical Examination of Effluent of Filter Tank No. 8. The following table contains the averages, by months, of the weekly analyses of the effluent of Filter Tank No. 18 A: 1890. December, 420,000 41° 42° .15 .0004 .0071 .21 .0368 .0000 1891. January, February,. March, .13 .0008 .0059 .0002 .0052 .12 .0004 .0040 .15 .0203 .0000 .18 .15 .0002 .0064 .0004 .0063 70° 73° .10 .0006 .0059 69° .12 .0006 .0081 ཌ ཋ ད མི བ .0230 .0000 .15 .14 .0230 .0000 .15 2 2 2 2 17 12 29 25 17 .16 .0235 .21 .0000 .17 22 .21 .0282 .0000 City water applied until Aug. 18, 1891; afterwards canal water. Experiments interrupted by high water in the river February 27 to March 1, March 12 to 16 and April 12 to 17; also March 20 to April 9, for repairs. A summary of twenty-five microscopical examinations of the effluent is given in the following table: Microscopical Examination of Effluent of Filter Tank No. 18 A. The averages, by months, of the weekly analyses of Filter Tank No. 20 A are given in the following table : 140,000 38° 43° .12 120,000 37° 45° .11 March, 60,000 37° 42° .11 April,. 100,000 42° 51° .13 May, 280,000 52° 57° .12 June, 300,000 60° 69° .11 .0008 .0059 Experiments interrupted by high water in the river February 27 to March 1, March 12 to 16 and April 12 to 17. |