June i, 1898.] THE TROPICAL AGRICULTURIST. 829 
THE HEAVIEST RAINFALL IN 24 HOURS: 
NEDUNKENI AND ITS 31 '72 INCHES. 
We direct attention to a very elaljorate and in- 
teresting Report given below made by Mr. H. Parker, 
Irrigation Assistant, P.W.D. and F'ellow of tiie Me- 
teorological Society, on the subject of the e.xtraordi- 
naryfall of rain during 24 hours in Decern I ler last at 
Nedunkeni in the Northern Province. The Re- 
port is addressed to Government and the subject 
having been a good deal discussed in our columns, 
the document has been placed at our disposal. 
Mr. Parker affords evidence to show that the record 
was very carefully taken and is an accurate, 
reliable one, Nedunkeni being most likely on 
December 15th-16th last, the centre of a cyclonic 
storm. Mr. Parker’s Report will prove of world- 
wide interest, especially to Meteorologi.sts and 
their Societies in all civilized countries ; for, 
as we have mentioned already, the number of 
cases on record, where more than 30 inches of 
rain has ever been recorded in any 24 hours, is ex- 
tremely limited; and Nedunkeni audits last De- 
cember’s experience is likely to go down very pro- 
minently to prostcrity, while the occurence will no 
doubt be freely discussed in scientilic papers for 
some time to come. 
^ 
ABNORMAL RAINFALL IN CEYLON; 
KAINFAEE OF 31-72 INCHES IN 24 HOURS, AT 
NEDUNKENI, N.P. 
FROM THE IRRIGATION ASSISTANT, C. I. BOARD. 
TO THE DIRECTOR OF FUBLIC tVORKS. 
Nabirittawewa, 16th April 1898. 
Sir, — My recent visit to the Northern Province 
has given rue an opportunity of making some en- 
quiries regarding the abnormal rainfall of last Decem- 
ber at Nedunkeni, and I have the honor to submit the 
following report on it ; — 
Nedunkeni, eleven miles down the southern road to 
Mullaittivu, and 122 feet above sea-level, is a small 
village at which there is a dispensary, with quarters 
for the Medical Officer stationed there, and two 
small bungalows for the use of Revenue and Public 
Works officiils when travelling. It is a little to the 
east of the dividing ridge of North-Central Ceyloa, 
and though itself in the catchment area of the 
eastern Per Aru, which flows through Tanuir Murippu 
Tank, it i.s only a little to the south-west of the 
point where three sepai’ate drainages meet. Forest, 
containing a thick grov.t i of high trees, extends over 
the neiglibourhood, and more especially for many 
miles from the south to the east, 
3. The staff at the dispensary consists of a Medical 
Officer, a dispenser, aud an hospital orderly. For 
about three years, a rain-gauge has been established 
in the grounds of the dispensary, and its records are re- 
gularly transmitted to the Public Works Office, and 
are published among the rainfall returns. 
4. I annex a sketch showing the position of the 
rain gauge, the dispensary buildings, and the ne.arest 
trees. 
5. Although the mean annual rainfall at Nedunkeni 
is probably little more than 60 inches, the fall for 
last December was 67’07 inches, and of this amount 
31-72 inches were measured at 9-30 a. ni. on December 
16th, as the rainfall of the preceding 24 hours. Un- 
precedented floods were caused by it throughout this 
part cf the district, and 162 tanks were breached by 
the water which poured over their embankments, 
while water passed from 18 inches to 2 feet 6 inches 
deep over the bridges on the northern road to 
Mullaittivu. 
6. The only rainfalls above 1.5 inches previously 
recorded in Ceylon according to the last published 
Annual Returns (for 1896) have been 18-75 inches, on 
December 14-15, 1896, at St. Martin’s estate, Rangalla, 
Feet 
Max : 
above 
Rainf.ill 
Pate. 
sea-level. 
in inches. 
136 
19 50 
Sept. 
8-9, 1884 
1,636 
■ 18 80 
Sept. 
8-9, 1872 
65 
18-.50 
Jau. 
15-16, 1876 
). 105 
17-90 
Oct. 
15-16, 1893 
'.P. 9 
17-60 
Oct. 
19 20, 1891 
.b. 729 
16-65 
Aug. 
6 7, 1886 
Central Province, 3,600 feet above the sea level, with 
an annual mean fill of 173-56 inchr-s, as entered in the 
Roturii of the Surveyor -General ; and the following 
amounts entered in the Public Works Departmens 
Return : — 
Devilane, B P. 
Padupola, C.P. 
Ambo.re, E.P. 
Avissawslla, S-ib 
The accuracy of t’neso last records of rainfalls has not 
been iiivestiga.ted, and it is quite uncertain to what 
extent they can be accepted. So far as Amb ire is 
concerned the method of measuring the rainfall that 
was in practice when I visited that tank last year was 
so rough as to render val-ueless any high measure- 
ments obtained there. 
7. The gauge at Nedunkeni is fixed on a plot of 
short thick grass inside the dispsiisarj enclosure. Its 
top, 5 inches in diameter, is 2 feet above the ground, 
and the mouth of the funnel has a vertical rim 2 in. 
high. The bottle will hold a rainfall of 41- inches, 
and is completely enclosed in a water tight receptacle, 
in which any surplus rain collects when the bottle 
overflows. The rainfall is measured in an ordinary 
graduated half inch measuring glass. 
8. The rainfall of December 15th began at Nedun- 
keni at about 6 o’clock in the morning, and con- 
tinued without intermission until some time on the 
following day. That which fell before 9-30 a.m. on 
the 15th was entered as usual to the previous day’s 
account. At noon, at 3 p.m., and at 6-30 p.m. the 
bottle in which the rain was collected was emptied 
into an ordinary wash-hind basin by the Medical 
Officer or the Dispenser, having overflowed into the 
receptacle at 3 p.m. (this water also being emptied), 
and being full at the other times. The orderly states 
that during the night, acting on instructions given in 
the evening by the Medical Officer, he emptied it 
twice. On the first occasio-n it had overflowed, and 
all the water was poured into the basin, which was 
then nearly full. On the second occasion, the bottle 
was full, and he poured the water into the ewer 
belonging to the wash-haud set, after first examin- 
ing the latter to see that it was empty. At about 
7 or 7-30 a.m. on the 16th, the Dispenser emptied 
the bottle into the ewer, and again at 9-30 a.m., 
when it was about seven-eighths full. The whole 
of the water was then measured by the Dispenser, 
in the presence of the Medical Officer and the orderly. 
The Medical Officer is now stationed atMankulam; 
the account that he gave me there pgreed with that 
of the dispenser and orderly. 
[Here Mr. Parker gives a sketcli of the station, 
to show the situation of the rain-gauge. — E d. P.A.] 
9. By a fortunate accident, this rainfall lias oc- 
curred at a station where there is the check of a 
quite unusual number of observers. Practically the 
only doubt that can be felt with regard to the all- 
important check of the number of times the bottle 
was emptied is with reference to the statement of 
the hospital orderly that he went out twice in the 
night to examine and bring it to the house. With 
respect to this it may be noted that the intensity 
of the rain from 9 30 a.m. to 6-30 p.m. on the 15th, 
was almost exactly 14 inch per hour. The Medical 
Officer informed me that heavy rain continued up 
to above 8 p.m., after whic’a it became lighter. 
According to the hospital orderly’s evidence, we have 
for the next 13 hours after 6-30 p.m.. an intensity 
of a' trifle more than 1 inch per hour, aud this is 
only about two-thirds of the intensity of the succeed- 
ing 2 hours up to 9-30 a.m. on the 16th. There is 
therefore no evidence that the statement of the 
orderly is untrustworthy ; on the contrary, it closely 
agrees with the aotu.al measurement made on the 
16th by the dispenser and the Medical Officer. If 
We accept his statement, a total of 6J bottles has been 
accounted for; tMs would bo about 31 inches, or 
