60 REPORT— 1870. 



sewerage for the removal of water-closet and liquicl house-slops, of rain-water 

 from roofs of houses, yards, and streets, there being about twenty-one miles 

 of sewers, which are calculated to meet the demands of the average annual 

 rainfall, but not of storms nor of periods of exceptionally heavy rains. 



The greater portion of the ashes is collected by the Commissioners daily, 

 and, together with the street-sweepings, is sold for the sum of <£200 annually. 

 A small portion only is collected by private individuals. The cost of collec- 

 tion coTild not be ascertained. 



The area contributing surface-water is approximately the area of the district, 

 3470 acres, and the average annual rainfall is 22 inches. The roadways of 

 the streets are macadamized ; they incline from the centre* to the curbs at a 

 rate of about 1 in 100, and are provided with guUeys connected with the 

 sewers. 



The subsoil is mostly gravel from 3 to 10 feet deep, overlying a bed 

 of gault from 120 to 135 feet thick. It was formerly saturated, but the 

 sewerage has di-ained the upper subsoil and dried many of the weUs that pre- 

 viously existed. Inquiries were made into the state of some of the wells be- 

 longing to private houses, and it was found that they were all contaminated 

 by sewage, owing to their proximity to the sewers in the streets and to the 

 drains on the premises, so much so, that the water cannot be used for drink- 

 ing but only for washing. 



The old sewers are of irregular forms, but the recent sewers are egg-shaped 

 or circiilar. They discharge at twelve separate outlets into the river Cam. 

 The inclination of these sewers varies from 1 in 120 to 1 in 2000. Deposit 

 has taken place to a considerable extent in the HiUs Eoad sewer, with an in- 

 clination of 1 in 2000, the deposit being, at the date of the examination, 7i 

 inches thick, and the sewage running over it 6 inches deep. The outlets of 

 the public and private sewers are all under the level of the surface of the 

 water in the Cam, consequently the sewage is backed up in the sewers for a 

 considerable distance, and the subsoil is constantly saturated with both water 

 and sewage in the lowest parts of the town. The authorities obligingly 

 offered to draw off the water of the Cam to enable the engineers to gauge and 

 collect samples of the sewage flowing from the sewers ; but as the bed of the 

 river could only be kept dry for a short time, the results would have been 

 unsatisfactory. Moreover, as the water which is backed up in the soil 

 would be discharged by degrees through the sewers, no correct result could 

 have been attained. 



There are two gaols (county and borough), a workhouse, a hospital, and 

 an asylum, aU of which are connected with the sewers. There are no fac- 

 tories nor special trades, but the slaughter-houses send their liquid refuse 

 into the sewers, and this on killing days is highly charged with blood ; the 

 solids from this source are mixed with ashes and carted away, 



BemarJcs hy a Sub-Committee, consisting of Messrs. Gkantham (CJiairman), 

 CoEFiELD, Hope, and Williamson. 



It is not the province of the Committee to prepare schemes for the sewerage, 

 or for the drainage of particular towns, and as the inquiries of the Committee 

 are stiU far from complete, it would be premature to make any suggestions 

 either in this or any other case as to the best means of utilizing the sewage 

 when collected ; but it is manifest from the foregoing Report that the sanitary 

 conditions of Cambridge, as regards its sewerage and drainage, are exceed- 

 ingly bad, and the low level of the greater portion of the town must make 



