IN THE MONTH OF FEBRUARY, 1852. 151 



Reservoir, through which, as has been before observed, the 

 whole had to be passed, was as follows : — 



Cubic feet. 

 From nine o'clock on the morning of the 4th to 2 p.m. 



same day, 5 hours, at 300 feet per second 5,400,000 



From 2 p.m. to 12 p.m., 400 feet per second for 



10 hours 14,832,000 



From 12 p.m. 4th, to 9 am. .^th, 450 feet per second for 



9 hours 14,580,000 



From 9 a.m. 5th, to 7 p.m. 7th, 68 hours, at 450 feet 



per second 93,960,000 



From 7 p.m. 7th, to 7 p.m. 8th, mean discharge 500 feet 



per second, 24 hours 21,600,000 



From 7 p.m. 8th, to noon 12th, 89 hoars, at 550 feet per 



second .. 176,220,000 



From noon 12th to noon 13th, 24 hours, at 450 feet per 



second 38,880,000 



Total 365,472,000 



The quantity of water discharged was equal to a depth of 

 6}f inches over the whole surface of the collecting ground, 

 averaging nearly H inch per day for the 5 J days during which 

 the rain lasted. 



The rain at Crowden Hall from the evening of the 3rd to 

 noon on the 9th, subsequently to which no materia! fall of 

 rain occurred during the period that the reservoirs were 

 being emptied, was 5^^ inches. To determine the precise 

 quantity of water due to the fall of rain, something must be 

 deducted for the yield of the streams, supposing no rain had 

 fallen. Their average volume, swollen as they were by pre- 

 vious rain, would have been about 60 cubic feet per second, 

 which, for 9 days and 3 hours would have amounted to 

 59,304,000 cubic feet, — equal to about an inch in depth over 

 the collecting ground, leaving the nett quantity of water due 

 to the rain 5| inches, — being ^ of an inch more than the 

 rain shewn by the Crowden Hall rain gauge. 



The results just given from calculations upon the discharge 



