Disease and putrescent air. Some principles which must govern the efficient ventilation of sewers, and the effective hygenic treatment of "sewer gas" : also, the sanitary ventilation of house drains and connections / by Thomas Rowan.

  • Rowan, Thomas.
Date:
1883
Catalogue details

Licence: Public Domain Mark

Credit: Disease and putrescent air. Some principles which must govern the efficient ventilation of sewers, and the effective hygenic treatment of "sewer gas" : also, the sanitary ventilation of house drains and connections / by Thomas Rowan. Source: Wellcome Collection.

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    I here is a principle here which must govern all successful ventilation, whether it be of sewers, tunnels, or buildings, and determines the proper relation of inlets and outlets. Beyond the fact that outlets should be taken from the highest point and inlets from the lowest, the position which inlets should relatively occupy to each other as well as to the outlets, has not been defined by any recognisable law or principle, but has been left to chance or empiricism. That principle to which I am now directing attention, but can only briefly dwell on here, may be defined as follows:—An outlet will draw but from the nearest inlet, and if this can supply the want created by the outlet, no further action can take place from other inlets, for the volume of air admitted to a sewer, or tunnel, or room, can only be equal to that abstracted from it. The following experiment will illustrate this :— A Take a tube, as shown at Fig. i, open at the two extremities A and D, and with tight-fitting corks in the openings B and C. At A create an induced current by means of an aspirator or small vacuum cowl, while holding a piece of smoking touch paper or tow at D. The smoke will immediately travel through the tube towards A, as indicated by the arrows. Uncork now the opening C, while still holding the touch paper at D, and at once it will be seen that but little smoke can be made to travel through the tube; the small amount of smoke that does pass down D makes its way slowly to C, where it again regains its original rapidity towards A.