TRANSACTIONS OF SECTION 6. 



803 



11 feet 9 inches. To maintain tbis a rainfall of at least 2 inches a month over 

 the three counties is necessary — that is, over 1,964 square miles, or 56,956,000,000 

 gallons. 



3. This gives some idea of the proper quantity of compensation water. The 

 Liverpool compensation water is 10,000,000 gallons a day, and 1,280,000,000 

 gallons a year in addition ; that is, a total compensation of 930,000,000 gallons a 

 year. This looks a large amount. The Liverpool gathering ground is 36 square 

 miles ; an inch of rainfall over that is 532,000,000 gallons. On Septemher 9 and 

 10, 1886, at three places in Montgomeryshire the rainfall was : — 



Inch Inch Inch 



September 9 1-01 -19 -90 



10 — MO — 



The effect of the 3 inches of rain was to raise the Severn at Diglis 4 feet for one day. 



4. Rainless periods and the efi'ect on the river. 



The following were the rainless periods for 1886 and 1887 at 15 places in the 

 Severn watershed : — 



1886. February. — Four places, 12 days. 



,, Three other places, 11 days. 



March 3 to 15. — Kain only fell on 4 days at 4 places. Except a fall of 



•40 inch, the whole fall was only -04 inch. 

 May. — No rain recorded anywhere from 1st to 6th. 

 June (from 23rd to July 7). — Only a total of '08 inch at 3 places. 

 August 18 to 31. — Only 'IS inch in the watershed, except at a place in 



Montgomeryshire, where a storm registered -27. 

 September 13 to 25. — No rain but at a place in Montgomeryshire, 1-68 



inch on 1 day. 



1887. February 6 to 13.— No rain. 



,. 13 to 17.— Only -08 inch. 

 March (from February 25 to March 9). — Only -02 inch on 2 days at dif- 

 ferent stations. 

 April 6 to 20. — No rain registered in watershed. 

 June. — No rain registered in watershed between June 8 and July 4. 

 July. — No rain from July 30 to August 12. 

 August. — No rain from August 20 to 26. 

 September 17 to 26. — No rain in watershed. 

 October. — Until 8th rain only fell at 2 places in watershed. 



„ 15 to 23. — Only rain in 3 places. Total at all, -09 inch. 

 November 12 to 19. — Only -12 inch at 6 places in watershed. 



3 F 2 



