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the main sewers which have manholes for cleaning purposes, traps being formed in connection with the manholes. These sewers are intended to carry off the house drainage and in part the rainwater. When practicable the rain flood water is carried off through open nullahs. The main sewer is provided with overflow connection with nullahs as a provision for floods. The main sewer finally runs out into the sea and discharges in the harbour. There is only one ventilating shaft in connection with the whole system. The system is defective in the following respects. That, owing to the want of ventilation the various traps must during heavy rains become unsealed by syphon action and sewer gases consequently escape freely into the streets through the manholes and gullies. And, that as the main sewer opens directly into the sea, there must result during the time of high tide, what amounts practically to a cessation of the working of the whole drainage system as owing to the low level of the site of the village the head or pressure from behind can effect but little in the discharge of the sewer. During this time there must be an accumulation of drainage water, as a considerable portion of the main sewer is then filled by the tide