Mr. Baldwin Latham. 



A pit gauge at Calne, as recorded in volume 41 of the 

 " Transactions of the British Association," is shown to have 

 collected 5 per cent, more rain than one at i foot above the 

 ground. In the collection of rainfall, therefore, it is important 

 that the height of the gauge above the ground should be 

 stated, as elevation above the ground may greatly influence 

 the amount collected. As a rule rain-gauges are now fixed I 

 foot above the ground level, which secures them from an 

 increase arising from splashing from the surface of the ground, 

 and also protects them from other inconveniences which may 

 affect the quantity of rain collected. 



The author, in carrying out the underground water investi- 

 gations at Croydon, found the level of the water under 

 the town fluctuates with rainfall after a dry period, and that 

 it also fluctuates in consequence of the effects of pumping 

 at the Croydon Water Works. It was a matter of importance, 

 therefore, to determine what fluctuations were due to rain as 

 distinguished from those due to pumping. In order to arrive 

 at this it was necessary to record the periods at which rain 

 fell, and in the recording rain-gauge which the author has 

 used for this purpose some other interesting matters have been 

 brought to light. 



Hitherto very few experiments have been made in this 

 country as to the rate at which rain falls, which is a point of 

 some importance, TJie author's registering rain-gauge not 

 only shows the time of day when rain falls, but also the rate at 

 which it falls. Since the 27th March, 1879, the period when 

 the gauge was fixed, there have been : — 



166 times when rain fell at a rate exceeding i*44 inches in 24 hours. 



161 

 159 

 153 

 107 



77 

 6z 



41 



32 

 22 

 18 



15 

 12 

 12 



ID 



ID 



5 



4 

 3 



when it fell at the rate of 



i-6o 

 I "go 



2"0 



3-0 

 4-0 

 5"o 

 60 

 7-0 

 8-0 

 9-0 

 io*o 



II'O 

 I2"0 

 13-0 

 14-0 

 15-0 

 17-0 

 IQ'O 



33-12 

 37'44 



