Published online by Cambridge University Press: 27 March 2009
Natural drainage periods, i.e. periods between consecutive cessations of flow of the Rothamsted 20 in. drain gauge, were selected for the months of June, July and August. All periods of from 2 to 13 days were taken.
A curvilinear relationship between the difference of rainfall and drainage (deficit) and rainfall was established.
Residuals from this curve showed no appreciable correlation with the mean air temperature, but there was some slight evidence that the deficit was increased by a decrease in relative humidity or an increase in wind velocity.
The residuals showed little correlation with drainage during the previous 3 weeks.