III. 



REPORT OX THE RAINFALL IN HERTFORDSniRE IN THE 



YEAR 1897. 



By JoHX HoPKrasoN, F.L.S., F.G.S., F.E. 3Ict. Soc, Assoc. Inst. C.E. 



Read at Watford, 22nd March, 1898. 



There are a few alterations in our rainfall stations, but the 

 number is the same as in the previous year, namely 44. Two 

 stations disappear from our list — Elm House, Tring, no reply 

 having been received to my applications for the return ; and the 

 Cowroast station of the Grand Junction Canal Company, omitted 

 owing to errors in the record. On the other hand there are two 

 stations added — the London Orphan A.sylum, Watford, and 215 

 St. Albans Road, Watford. Mr. Fordham's gauge at Odsey is 

 a new one, placed three feet north-west of the old one, and on the 

 same level. 



The number of daily records received is 35, which is the same 

 as in the previous year. 



Particulai's of the 44 rainfall stations, and the monthly and total 

 rainfall and number of days of rain in the year 1897, as usually 

 computed, are given in Tables I and II, pp. 25-27. 



A supplementary table (Table III, p. 28) gives eight other 

 records of the total rainfall in the year. Two are the records of 

 additional gauges at Rothamsted, and six are taken from Symons' 

 'British Rainfall, 1897.' 



The mean rainfall in the county in the year 1897 was 24'87 inches. 

 This is 1*87 inch below the average for the decade 1880-98, and 

 1-56 inch below that for the half-century 1840-89. The year was, 

 therefore, one of rather small rainfall. The mean number of wet 

 days in the year was 166, being two less than the average for 

 the twenty years 1870-89. 



The most remarkable featui'e in the year's rainfall is the very 

 small faU in October and November, which are usually about the 

 wettest months in. the year. !N^ext to these months in amount of 

 rainfall usually comes July, and this month, in 1897, had the least 

 fall in the year. That a single month should differ greatly from 

 the average is by no means exceptional, but it is remarkable that 

 two months in succession in the (usually) wettest part of the year 

 should have together anything like so little rain as 7*8 per cent. 

 of the year's fall, as was the case with October and November, 

 1897. As a rule the second half of the year is much the wetter 

 of the two, but this year the first half had 56 per cent, of the 

 year's fall, while the second half had only 44 per cent. 



Droughts in 1897. — Accepting as before Mr. Symons' definitions 

 of "absolute" and "partial" droughts, there were two absolute 

 droughts in 1897 and there was one partial drought, but they were 

 not general over the county, one of the absolute droughts occurring 



