Hints to househunters and householders / by Ernest Turner.

  • Turner, Ernest.
Date:
1884
Catalogue details

Licence: Public Domain Mark

Credit: Hints to househunters and householders / by Ernest Turner. Source: Wellcome Collection.

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    dividing by two, just multiply by 144, and then either divide the result by 277-274 or multiply again by -003607. But when you have done so there will be no harm in bearing in mind that this theoretically more accurate result will practically be most likely wider of the mark than the simple rule of thumb. The result shown is the precise amount of water due on the scale of the general rainfall. But roof-slates are in summer-time often almost hot enough to butn your fingers, and a good deal of the rain falling on them at such times is, of course, lost by evaporation. In the rough mode of estimate first suggested the error in the calculation and the loss by this evaporative process more or less compensate each other. An “ inch of rainfall ” it may be noted, means a little more than 4^ gals. (4-673) per square yard ; or roughly, half a gallon per square foot. Rain-water tanks are constructed more cheaply underground than above, and preserve the water at a more regular temperature ; but they are much more liable to unrecognised leakage and to pollution. Above-ground tanks are free from these disadvan- tages, and are more easily examined. The best shape is round or polygonal. An excellent material is concrete, consisting of six parts gravel or broken stone to one of Portland cement; but it is not every bricklayer who can mix it. Every tank should be carefully covered, and a man-hole provided.