98 



J. nOPKINSON HEPOET OX THE EAINFALL. 



The localities are arranged in the same order as before, i.e. 

 grouped according to Mr. Pryor's proposed botanical divisions* and 

 the distance from Watford. The same four divisions and twelve 

 minor districts as in the previous year are represented. 



The accompanying table (p. 99) gives the monthly and annual 

 rainfall f at each station. It will be seen to have been more 

 evenly distributed over the year than in 1876. January and 

 November were the wettest months, and July and August follow. 

 June and September were the driest. 



The next table gives the mean rainfall for each of the larger 

 divisions or main river-basins, and also for each of the smaller dis- 

 tricts or lesser river-basins and their subdivisions. 



f Lower Lea 29-86 



I Upper Lea 29-21 



L« ^"H "=":::: ^^ 



Rib 29-84 



[Ash 29-29 



( Lower Colne 31-79 



Colne 32-80 Ver 34-39 



( Bulborne 32-23 



Thame 34-63 Thame 34-ti3 



^""'^ 28-36 j Cam 



27-04 



In 1876 the distribution of rain in the main river-basins was — 

 in the Colne 32-28 inches, Thame 34-09, Ouse 28 52, and Lea 

 29-08, showing that the rainfall was in about the same relative 

 proportion in each district in the two years, the Thame receiving 

 the greatest amount of rain, then the Colne, then the Lea, and the 

 Ouse having the least. 



Of the 26 observers 22 give the number of days in each month 

 on which -01 inch of rain or more fell. The mean of these for the 

 different months is as follows : — 



giving a mean for the year of 193-3 days, — about \Qh days more 

 than in 1876. The least number of rainy days Avere at Therfield 

 (150), 8t. Albans (165), and Hoddesdon (173); the greatest, at 

 Oaklands, Watford (214), Nash Mills (214), and Harpenden (220). 

 The numbers nearest the mean were at Eickmansworth (190), 

 Much Hadham (191), and Odsey (193). 



These 22 returns also give the greatest amount of rain which 

 fell in any one day in each month ; and from these particulars the 

 following table is compiled. It shows at what station there was 

 the greatest fall in 24 hours in each month, with the day of the 

 month and the amount of the fall. 



Jan. 3.— Great Gaddesden 0-86 



Feb. 12.— East Barnet 0-50 



Mar. 29.— Rickmansworth 0-48 



April 9.— Welwyn 0-76 



May 16. — Bayfordbury 0-75 



June 30. — Buntingford 0-64 



July 31.— Therfield 1-04 



Au?. 25.— East Barnet 1-16 



Sept. 3. — Kensworth 1-45 



Oct. 29.— St. Albans 1-15 



Nov. 11. — Berkhampstead 1-42 



Dec. 28.— Therfield 0-81 



* ' Transactions,' Yol. I, p. 67 ; and map, Plate I. 

 f The amounts entered as rain include melted snow. 



