19 
bably be determined some two or three weeks earlier by 
the rise of the water in a well in the upper portion of 
the district to what it would be at a point near where 
the Bourne usually breaks out. Consequently with a 
continuity of observations, and knowing the level of 
the waters of the upper wells, there is no reason ‘why 
any person in any district should not be able to predict 
with absolute certainty as. well as the Author has done 
from year to year, the exact time when a Bourne. will 
occur, and its probable volume when it breaks out. 
The period’ of high water in a well at Cambrian 
House, Caterham, has been ascertained to be from 
twenty to forty-five days before the time of high water 
in a well at the “‘ Rose and Crown,” Coulsdon, lower 
down the valley, and located close to the place where 
the Croydon Bourne first breaks out. The Author also 
ascertained that when the water in the well at Cambrian 
House well rose to a level of 340 feet above ordnance 
datum there would be a small Bourne flow in Caterham 
Valley, and when the water in this well rose to 370 feet 
above Ordnance datum, then the flow would increase 
and extend up the valley and there would be a flow in 
Marden Park. : 
The owner of Cambrian House well objected after a 
time to his well being measured, and covered it over, 
and would not suffer any provision to be made for its 
future measurement. 
The following table gives the years when it has been 
reported that the Croydon Bourne has flowed, and gives 
the name of the person on whose authority the state- 
ment is made: 
Prediction of 
Bourne flows, 
Cambrian 
House well. 
* Rose and 
Crown ’’ well. 
Level of water 
to produce 
Bourne flow. 
