Sessional_Paper_1902 — Page 563

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in a mass of clay-puddle. To test in this manner, will occupy twenty-four hours or more, whilst, given a proper testing-press and appliances, the hydraulic test is usually effected in one or two minutes.

In addition to the hydraulic test, pipes should be callipered and examined for straightness, and no pipe deviating, more than some specified amount from the standard dimensions, must be accepted. I shall be happy to furnish, when I return to England, a copy of the Standard Specification, which has been used for some time past, for sewer-pipes manufactured for works, carried out under my direction. The standard regulations concerning house-sewer construction, though not textually applicable to Hongkong, might also be of use.

arrange-

467

84. It is perhaps now too late to introduce the system which has been As to the adopted elsewhere, under which all pipes and appliances are imported by the Sewer- ments for

inspectiou age Authority.

and testing.

use.

I am of opinion, therefore, that all pipes should be inspected and tested before There would be difficulty in testing at the works of the manufacturer, as many of them are at a great distance. Probably, the best plan would be to provide a depôt, at which testing could be effected. This might be worked, on the lines of a Bonded Ware-house, contractors stacking pipes there, and taking them away after testing as they required them. It would not be necessary that each individual contractor should take away the identical pipe that he brought in. He might merely obtain a receipt for so many approved pipes, and be entiled to draw against the

same.

of standard

and

85. To establish a Standard of Quality, it will be well to import a small con- Importation signment of pipes, bends, junctions, traps and hoppers, made to the specification, pipes, traps and of the standard pattern, which has been adopted elsewhere. I have adopted a appliances. five-inch pipe, as the universal size for house-sewers. I am of opinion that a four- inch pipe is too small, and a six-inch too large. A five-inch house-sewer suffices for almost every class of tenement. Formerly there was difficulty in obtaining five- inch pipes. Now this is not so. Thousands have been supplied to works abroad: and numerous Local Authorities now specify five-inch house-sewers. I have largely employed this size for street-sewers.

86. I find that even Licenced Contractors do not pay sufficient attention to house- Fee for

inspection. sewer construction. The Sanitary Surveyor is often called upon to inspect house- sewers, that are obviously imperfect, and which should never have been reported as ready for inspection, frequently he has to pay two, three, or more visits, before he can finally pass the work. These repeated inspections, not merely waste the time of the Government Officers, but cause inconvenience to the owner, as they delay construction, and postpone the occupation of the tenement. If the pipes and material, were inspected and tested, before use, there is no reason why a house- sewer should not be passed, at the first inspection. Failure so to do, must be due to want of care, on the part of the contractor, for which he should suffer. I therefore recommend that a fee of $10 be paid by the contractor, to the Government, for every inspection, after the first.

1

houses to be

87. House-sewers, running under houses should be made of cast-iron pipes, Drains under properly coated with Dr. ANGUS SMITH'S composition. The present practice in of Cast-iron. such cases, is to bed the ordinary sewer-pipes in limé and red earth concrete. This is not good enough. If cement were used, the cost of bedding in concrete, would be nearly if not quite equal to the extra cost of the iron pipe. Again, bedding in concrete necessitates or ought to necessitate two inspections, one before the concrete is put in, and a second after so doing to see if the pipes have been dislocated by ramming in the concrete.