92, ANNUAL REPORT 
@ 
In 1894 over a mile of ten-inch and twenty-four inch pipe of-this make 
_ was laid at Scarborough-on-Hudson, of a concrete composed of 1 cement, 
2 sand, 5 stone at a cost of 30,cents per foot for the Io inch and 95 cents 
per foot for the 24 inch sewer. 
Edward Mahun, C. E., constructed a large egg-shaped sewer, 2 feet 
by 3 feet and 2 feet 10 inches by 4 feet 3 inches in dimensions, of mono- 
lithic concrete, for the city of Victoria, B. C., in 1891. This shows that 
several engineers began the work at about the same time. 
A large concrete storm sewer was constructed for Maelbeek creek, 
Brussels, Belgium, in 1895. This sewer had a circular form with a 
diameter of about 15 feet in one part, and a section in another part of 29 
feet 7 inches wide by 9 feet high. The remarkable feature of this large 
concrete structure was the leanness of the concrete. The foundation was of 
I part cement, 6 parts sand and 12 parts gravel, while the sides and arch 
were of I part cement, 4 parts sand and 8 parts gravel with a 1 inch face 
of I to I mortar. 
Reading, Pa. —In 1806 the city of Reading, Pa., constructed a large 
amount of concrete sewers ranging in size from an oval sewer 4 feet 8 
inches wide by 7 feet high to a circular sewer 14 feet in diameter. 
Some $250,000 to $300,000 was expended in combined sewers for the city. 
These were plain concrete sewers—no metal being used to reinforce the 
concrete. The concrete -was proportioned as follows: I part cement, 
3 parts sand and 6 parts broken stone or gravel. The work was plastered 
upon the inside with cement mortar after the forms were removed. This 
plaster coat has peeled off in a very few places of limited extent, otherwise 
the appearance of the sewer is as good as when it came from the forms. 
The writer visited Reading in the summer of r902 and examined 
the sewers, but could see no appreciable evidence of wear or disintegra- 
tion except as already stated. The engineer said there were velocities 
ranging up to 19 feet per second or greater, in some places in these 
sewers. At the outlet an abrupt 90 degree bend in the sewer shows 
no evidence of wear. 
At the time the contract was let there were 15 bidders upon the 
work. Alternate plans were drawn, one for brick, the other for concrete 
—the 14 foot sewer with 4 rings of brick or 18 inches concrete, the 10 
foot sewer with 4 rings of brick or 15 inches of concrete, the 6 
foot sewer with 3 rings of brick or to inches of concrete. The average 
of the bids upon the concrete was 85 per cent. of the bids for building 
the same sewers with brick. Comparing each bidder’s prices upon con- 
crete with his prices upon brick sewers, the bids upon concrete ranged 
from 67 per cent. to 103.6 per cent. of the prices bid for brick sewers. 
Columbus Sewers.—A brief description of the concrete sewer work 
now under construction in Columbus, Ohio, should also be given. 
