293 
The success of this was so complete thnl extended sub-drainage was 
decided on. 
Tile drainage work was started early in 1906, but it was not until 
towards the end of the year that sufficient was laid to begin to show 
its effects. During 1907 the work was vigorously conducted. The 
figures given below will show the effect produced. It must be stated 
that the figures given for 1906 do not fairly express the conditions. 
In some districts hospitals had not yet been erected ; also the coloured 
employees had not yet realised the value of the hospitals, and would 
lie about the villages and camps. It was not until a systematic 
inspection was started whereby the District Physician and Sanitary 
Inspector would visit the houses and camps, sending all cases to the 
hospitals, that true statistics became available. The month of March 
is selected as being towards the end of the dry season, and August as 
the period during which the fever rate reaches the highest point. The 
figures show the percentage of employees passing through the 
hospital during the month. The third column shows the annual 
average per 1,000 of deaths from malaria, based on the number of 
deaths in August for the years shown : — 
March. 
1906 
6-32 
1907 
4'16 
1908 
1-23 
August. 
Annual Average per 
1000 of Deaths. 
901 
10-55 
5’33 
5-05 
3‘43 
2-44 
As a rule, the breeding areas giving the greatest trouble here, 
besides small streams, swamps, and low-lying, soggy land, are seeps 
on the sides and at the bases of hills from water following small areas 
of impervious strata. At Ancon this is specially marked. , 
difficult to find, and the smallest depression holding water can bree 
enough Anophelines to send up the rate for a given camp. 
The tile used was of three s..,es: 4". 6". -d .0'', ^ 
unglazed. Where the tiles had to receive seepage water on y, 
could be laid at grades as low as one-half per cent, care being 
taken to place a wisp of grass over the joints. If the soi was v ry 
