A.—4a
Fig. 3. —Old drainage, with new system being installed. Note the 4 in. earthenware pipe, then a 6 in., and finally a 4 in. pipe with 90 per cent. bend. Earthenware instead of castiron. No terminal vent. No anti-siphon vent.
Fig. 4. —This manhole shows the work of a Samoan-born labourer, after a little more than twelve months' training.