OK THE MEDICAL TOPOGRAPHY OF SINGAFORE. 
455 
another deduction from these tables, that if the wind during the N. 
E. monsoon blows less frequently and steadily from the N.E. then 
it blows, more frequently and steadily from the N. W. The same 
with the S.W. monsoon, when the wind fails in that direction, it is 
to be found blowing from the S. E, 
On examining that table another and important fact will be no¬ 
ticed that in April and October we have the winds from the north 
and south nearly balancing one another. In April we have winds 
blowing from the direction of N.W. and N.E. 1852 hours, and from 
the S.W. and S.E. 1868 hours. In October we have them blowing 
from the N.W. and N.E 1567 hours and from the S.W. and S.E. 
1395 hours. These two months have more variable winds than any 
other of the 12 and affect the health of the community more. 
The last remark I would make on this subject is that the wind 
in changing from the N.E. monsoon to the S.W. seems to do so by 
gradual changes from N. E. to N. N. E. north, then N.W. to west, 
and then to S.W. And in changing from the S.W. monsoon to the 
N.E. retraces its progress by retaining its westerly direction and not 
reaching the N.E. by north than S.E. and east; but adopting the 
same direction by which it reached the S.W. from N.E. viz., a wes¬ 
terly. 
The next important point in a medical topographical account is 
the fall of rain and quantity of moisture in the atmosphere. It is 
genet ally stated in Meteorological works that at or near the equator 
the quantity of rain is much greater, but the number of rainy days 
much less than in more northern latitude. Humboldt gives 96, 80, 
29 and 17 as the annual depths of rain at the respective latitudes of 
0°, 19°, 45° and 60°. The Journal de Physique says, “ 6 From 
north latitude 12° to 43° the mean number of rainy days is 7S-g-; 
from 43° to 46° the mean number is 103 ; from 46° to 50 p , 134 ; 
and from 51° to 60° 161.” According to Dr. Ward, the average 
number of rainy days for Pinang was 182, the least in one year 160, 
the greatest number in one year 209. Colonel Low informs us that 
the rain fell almost every day betwixt October 1789 and June 1790, 
betwixt May 1833 and April 1834, rain fell in 145 days on the 
