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lons per day. The amount would then be 308,200 gallons per day. If to this we add the average amount actually pumped per day for the Highland high service, as shown by the records for May, before the Beacon Hill district was added, which was 82,640 gallons; the total requirements would then be, 390,840 gallons per day, by a most liberal estimate, and only 53 per cent. of the average daily amount actually pumped in the month of December. There are probably fifty gates in all, required to separate the high and low service, with a difference in pressure on the two faces of 40 pounds and upwards per square inch; and, unless all these gates are perfectly tight, it is evident that, with such a pressure, the leakage must be very large from the high to the low surface; and it is this, in my judgment, and not a wasteful use, that causes the enormous requirements of the high service.

The pumping records show that the hour of greatest draught generally falls between 8 and 9 o'clock A. M., and that the hour of least draught, between the hours of 2 and 3 o'clock A. M. Thinking it might be interesting to know the relative consumption on different days of the week, I have taken considerable pains to compile the following statement:

Statement of the average daily number of gallons of water pumped for the high-service supply on each day of the week from June to December inclusive, arranged to illustrate the comparative draught on the several days of the week.

Month.

Monday. Tuesday. Wed'sday Thursday Friday. Saturday. Sunday.

June,

July,

745,479 687,234 706,661 678,977 654,786 726,683 543,731 692,948 661,919 624,600 644,927 662,916 640,528 603,872

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October,.

643,465

November,

December,

674,927 630,176
733,435 647,908 668,926 656,801 647,378
791,826
729,510 732,213 711,101 725,097 765,788 692,345

625,271 630,166

660,488

582,132

683,296

598,915

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From the foregoing statement it appears that the days of the week arranged in the order of the greatest average consumption stand as follows:

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The average consumption on Mondays is 19 per cent. greater than on Sundays, and about 8 per cent. greater than the average of the Tuesdays, Wednesdays, Thursdays and Fridays, which do not vary much from each other.

Before the Beacon Hill high-service district was connected, the night consumption (from 12 o'clock midnight to 5 A. M.) was found to average 10 per cent. of the day consumption. Since the Beacon Hill district was connected, the

proportion of night to day consumption has increased to 20 per cent.

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In January, owing to the low state of the water at the lake, and the consequent fears of a scarcity of water, it was decided to reduce the hours of pumping; therefore, from the 13th of January to the 1st of May the pumps have averaged only 18 hours per day, and the amount pumped has averaged 493,250 gallons per day, equal to an average of 27,403 gallons per hour of pumping time. The daily average amount pumped in December was 735,274 gallons. It thus appears that the reduction of the pumping time one quarter has reduced the amount pumped from 735,274 gallons per day to 493,250,- a saving of 242,024 gallons, or 32 per cent.; or, more concisely, a reduction of 25 per cent. in the pumping time reduced the amount pumped 33 per cent. This result does not appear reasonable; for the reduction in the pumping time takes place during that portion of the night when the draught is lightest, and it would be naturally supposed that, if there were any difference between the percentage of the reduction of the amount pumped and the percentage of the reduction in the pumping time, it would be the other way, — that is, the amount pumped should be reduced by a smaller percentage than that of the reduction of the pumping time. But the fact is, without doubt, that a considerable portion of the percentage of reduction in the amount pumped is attributable to other causes independent of the mere reduction of the pumping time: such as a general economy in the use of the water caused by fears of a water famine, and the stoppage of the leak on the 30-inch gate in Tremont street, which finally broke on the 28th of January, and the supply to Beacon Hill was cut off for three days. That there must have been considerable leakage at this point is evident from the records of the amount pumped before the break was discovered, and the amount pumped immediately after the repairs were made. For instance, the pumping

time was reduced on the 13th of January, and the break was discovered on the 28th, during which interval the amount pumped per day averaged 511,000 gallons; while, for the eleven days immediately succeeding the repairs, the average amount pumped per day was only 461,000 gallons, a reduction of nearly 10 per cent., and, undoubtedly, attributable to the stoppage of a leak which may have existed for a long time.

WESTERN DIVISION.

The Superintendent's Report will furnish all information relative to the condition of the grounds and various structures on this division.

The work of marking the bounds of the city's property on this division still remains incomplete, and should be finished as soon as possible.

The annual examination of the interior of the conduit was made last month. The section from the Lake to the Waste Weir at Dedman's Brook was examined by J. Mains; from Dedman's Brook to West Pipe Chamber, in Needham, by J. A. Wiggin; from the East Pipe Chamber to Newton Centre Waste Weir, by Henry Manley; and the remainder to Brookline by Albert Stanwood, Superintendent of the Western Division.

The following is a transcript of the records made by the several examiners, from which it appears that the conduit is generally in a cleaner condition, and that no essential changes in its stability have occurred:

Report of J. MAINS, from the Lake to Dedman's Brook Waste Weir.

Entered the conduit at 8.50 A. M.

Between the entrance and Station 1 is muddy.

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Between 52 and 53 is a man-hole, at which is a bad leak. 57 and 58 are three small fissures, which need to

be pointed.

Between 66 and 67 needs repointing on the right.

66

71 and 72 is muddy.

97 and 98 is muddy.

115 and 116 is muddy, then clean to 136.

Near 140 is a large willow root growing.

Crack about inch wide near last man-hole.

At 142 is considerable mud.

Between 152 and 153 is a small crack in top, extending to Dedman's Brook Waste Weir, which we reached at 11 A. M.

Report of J. A WIGGIN, from Dedman's Brook Waste Weir to Newton Lower Falls.

Entered the conduit at 9.45, April 14, 1871.

From 169 to 170 are several small cracks in top, some of which have been repointed, and have not started.

Between 178 and 181 are several cracks in top, some of them being nearly or quite inch wide, others quite fine. From 182 to a little beyond 183 are several cracks, one of which has been repointed.

A little this side of 247, and extending about 50 feet, is a crack on top arch, left side, which in some places is nearly an inch wide.

Between 272 and 276 is a large crack, which has been repointed, which has not started any.

There is considerable sand along here.

What should be numbered 289 is numbered 282.

(From 12 to 14 are several large cracks, which have been repointed, but I think have started a little in places.)

Conduit quite muddy on bottom, from 16 to 183. From 53 to a little beyond 54 are two cracks in top, in some places quite fine, and in others about inch wide. 1

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