Introduction; Seasons and Winds. 
23 
especially on the table-lands. The warmth of the day itself is also subject to 
more or less variation, according as the moisture out of the First Zone rises 
sooner or later and in greater or less quantity, which, forming into clouds, inter- 
cepts the rays of the sun. Owing to the lesser heat and to the ground also 
being less damp, less vapour rises here than in the First Zone and consequently 
the atmosphere in general contains less moisture, the mean quantity of vapour 
being 15-7 grammes to the cubic metre, while 2F15 grm. at the lower and 
16-88 grm. at the upper boundary are necessary for saturation. The degree of 
moisture also varies much in different localities; it is much greater over the 
wet rice-fields (‘sawahs’) and dense woods than over stretches of grass or ‘alang- 
alang’, or over plantations of shrubs (tea, coffee). Also the masses of mist driven 
up from lower territories by the sea-breeze produce great differences. These 
mists condense here more quickly than in the warmer temperature of the First 
Zone, and often very heavy storms and showers suddenly result. As to this 
division it should be remarked that in the west part of Java the atmosphere is 
much damper than in the eastern portions of the island. The West Monsoon 
in the highest parts of this Zone is already felt in less force, and consequently 
the difference between the seasons (the wet and the dry) is here much less 
marked than in the lower districts, and even when the West Monsoon is in 
full force in the First Zone, the East Monsoon (the Trade-wind) often blows 
here for days in succession. 
“In the Third or Cool Zone the mean temperature is 18-7*’ C. (65-7® F., 
14-9** R.) at the lower and 13*^0. (55-4*^ F., 10-4*’ R.) at the upper boundary. 
The difference of temperature between day and night is here much less marked 
than in the First and Second Zones; the plateau of Mt. Dieng (6300 ft.) pre- 
sents an exception to this rule, the difference here being so great that the dew 
on bright nights sometimes freezes into rime. In this Zone the air, which, in 
consequence of the diminished warmth cannot carry so great a quantity of water, 
is entirely saturated with water-vapour (16-88 grm. to the cubic metre at the 
lower and 11-60 grm. at the upper boundary). The mists rising from the lower 
regions condense here to such an extent that this Zone might literally be called 
the Zone of Clouds. They sometimes begin to form as early as nine o’clock 
in the morning, especially on declivities covered with forest; from 11 or 12 till 
2 or 3 o’clock everything is covered with thick fog, which discharges itself — 
often simultaneously in different places — in storms of thunder and rain, after 
which alone the sun makes its way again through the clouds. But when the 
clouds are not broken up in this manner, so thick a fog covers everything for 
the rest of the day that it is impossible to distinguish an object at twenty-five 
paces, and it is not till after sun-down that the fog settles on the earth as dew. 
This, however, is more particularly applicable to the lower parts of this Zone, 
where the clouds gather most thickly; they seldom ascend to the upper parts, 
and then in less quantity, in consequence of which the showers there are rarer 
and less heavy. The influence of the West Monsoon is here almost entirely 
