It was considered dÃ©classÃ© to refer to one's own townhouses, estates or villas (or those of friends) as mansions and modern etiquette books still advise that the terms house, big house or great house be used instead.
Waste weir. A waste weir on a navigable canal is a slatted gate on each canal level or pound, to remove excess water and to drain the canal for repairs or for the winter shutdown.
Access to lock and levy. The function of the lock and weir is to maintain a constant water level in the canal system (approx 400mm above mean sea level) independent of the high and low tides which occur in the river, and to provide for travel by marine vessels between the river and canal system.