Contents preface (VII) introduction 1—37

Fig. 2.3 Tipping bucket rain gauge
(ii) Weighing bucket rain gauge : This gauge (Fig. 2.4) has a system by which the rain that falls into a bucket set on a platform is weighed by a weighing device suitably attached to the platform. The increasing weight of rain water in the bucket moves the platform. This movement is suitably transmitted to a pen which makes a trace of accumulated amount of rainfall on a suitably graduated chart wrapped round a clockdriven revolving drum. The rain-fall record of this gauge is in the form of a mass curve of rainfall (Fig. 2.5). The slope of this curve at any given time gives the intensity of rainfall at that time.

HYDROLOGY

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Catch bucket

Cover
Platform

Weighing device

Revolving drum

with record sheet

Pen arm
Base

Fig. 2.4 Weighing bucket rain gauge

Accumulatedrainfall(mm)

160

140
120

100
80
60
40
20
0 0 1 2 3 4 5 6 7 8
Time (Days)