; and it is immaterialwhether a grating be fixed to the top of the well or not.It is found in practice, however, that an open drain-ventilator of this description very close to a house 30 Sanitary Arrange7nents for Dzvellings. sometimes proves a nuisance. Another method ofachieving the same end,… … a water-seal; that is, a small body of water is interposedbetween the air of the sewer and the respirable atmo-sphere. There is a ready-made article, which comes suf-ficiently near, for most practical purposes, to what iswanted; and this is sketched in section and elevationat fig. 25. For instance,…
