78 
FETCH : 
or two years. All the trees were rested, i.e., not tapped, 
from February to June, 1912, after which tapping was 
resumed on the trees Nos. 9 to 16. In October, 1912, tapping 
was begun on trees Nos. 4 to 8. In August, 1913, trees 
Nos. I, 2, 5, 10, 11 were felled. 
The girths of the trees, at a height of 6 feet, varied from 
19*8 to 44 ‘3 cm. The difference were not in any way 
related to the position of the trees, both the largest and the 
smallest trees being situated in the same group. Tree 
No. 4, girth 20*2 cm., stood next to tree No. 9, girth 44*3 cm. 
Measurements were taken to the nearest millimetre. The 
results have been grouped in periods of four weeks each, or 
thirteen for the year. The curves on Plates VIII. -XI. show 
the total increment in millimetres from the beginning of the 
year up to the end of each four- week period as ordinates, at 
distances of 1 centimetre for each period. The curves for 
each tree for the consecutive years 1912, 1913, 1914 are 
grouped together under one another. 
On Plate XII. the total increment from the beginning of 
the year is given for each week for the months January to 
March, the curves of the three years, in the case of each tree, 
being arranged on the same horizontal line. As before, the 
ordinates represent the actual increment in millimetres, while 
the weeks are represented by distances of 5 millimetres each. 
The minimum temperature at Peradeniya ranges from 
about 68° F. to 73° F., and the maximum from 86° F. to 91° F. 
The rainfall is divided between two distinct periods, corres- 
ponding to the north-east and south-west monsoons. January, 
February, March are usually dry months, the temperature 
gradually increasing during that period. April should be wet 
and hot, but rather less rain falls in May. In June and July 
the heavy rains of the south-west monsoon prevail, and the 
temperature falls. August and September have only about one- 
half the rainfall of June and July. In October the rains of 
the north-east monsoon set in, and continue into December. 
There is thus, on the average, one distinctly dry period, 
January-March, and two periods of heavy rain, June-July 
and October-November. The coldest nights and the hottest 
days occur in the dry period. 
