755 GENERAL REPORT ON THE RESIDENCY OP SINGAPORE. 
Height 
of water 
fallen 
from the 
atmos¬ 
phere in 
1 year. 
Name 
of 
Rivulet. 
Quantity of 
water delivered 
into the sea in 
cubic feet du¬ 
ring one year. 
Superficies of 
country drained 
in square feet. 
Quantity of rain 
that falls on the 
superfecies drain¬ 
ed, in cub. feet 
during one year. 
Part9 of 1 hun¬ 
dred lost by ab- 
sorption & eva¬ 
poration 
92 in¬ 
ches. 
BrasBassa 
Rochor,. 
Balestier. 
201,744,000 
978,200,000 
397,912,000 
49,501,760 
213,147,540 
110,250,000 
380,513,493 
1,634,131,140 
845,250,000 
4 T 
TO 0 
—first, because I am not in possession of the beautiful instruments 
called Tachometers now used for these purposes by Engineers in 
Europe, and consequently had recourse to the old methods—secondly, 
the difference of the fall of rain may be greater at the heads of the 
rivers, (though difference of level is not much) than at their 
mouths, near which the Pluviometer of the Singapore Observatory 
was placed, further the measuring of the fall of rain is in itself 
subject to great variations. Thus the quantity collected in a gauge 
on the top of York Minster from February 1833 to February 1834 
only equaled 14,963 inches, while perfectly similar instruments on 
the top of the museum of that city, and on the ground gave 
relatively 19,852 and 25,706 inches* and again the inequality of 
the quantity of water passing down the rivulets at various times when 
affected by heavy rains unless constantly watched must add greatly 
to the inaccuracy—though this cause is of less account here where 
the jungle and marshes tend to keep back the water, which would 
flow rapidly to the sea in clear and well-drained countries, where no 
obstructions like these exist. With due allowances therefore the 
following deductions may be taken, that a square mile of surface 
in Singapore delivers to the sea about 100,000,000 of cubic feet 
per annum of water which would be available for mechanical 
power or irrigation &c., and that of the quantity of - water that falls 
from the atmosphere— T g§ds or nearly § is either reabsorbed by 
that element or decomposed by the processes of vegetation. The 
loss by absorption and evaporation has been estimated by various 
authors in very different proportions in other parts of the worldf 
thus the writer in the Edinburgh Encyclo. estimates it in Italy 
at fth and in Scotland at |th. In England it is estimated at gth|. 
At Liverpool it is estimated at | § and in the marsh lands of 
England it is estimated by Mr Glynn at §ds.l| - 
* Physical Geog. Eney. Britannica. 
t Physical Geog. p. 520. 
$ Cresy’s Enclo. of Engineering, 
C. E. and Archt. Journal vol. xr p. 188. 
Do. p. 301. 
