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THE EAINFALL ON TABLE MOUNTAIN. 
By Thomas Stewart, M.Inst.C.E. 
(Read June 19, 1912.) 
Observations of the rainfall on Table Mountain were first taken in 
January, 1881, when the late Mr. John G. Gamble, Hydraulic Engineer 
for the Cape Colony, placed a rain-gauge at a point known as Disa Head, 
which is about 2,500 feet above sea-level. During the month of May of 
the same year another gauge was erected at a station called Waai Kopje, 
which is about 3,100 feet above sea-level and about half-way between Disa 
Head and the top of the mountain. In September and October of 1884 
two additional gauges were erected — one near Kasteel Poort, 2,483 feet 
above sea-level, and the other at a station called St. Michael's, 3,050 feet 
above sea-level. These four gauges were the only ones in existence until 
1888, when I placed another gauge in the Disa Valley near where the 
middle Wynberg storage reservoir has since been built, and about 
1,500 yards from the Disa Head gauge. My reason for placing this 
gauge so near to the Disa Head station was that the amount of rainfall 
registered at the Disa Head gauge appeared to be considerably below that 
which fell at a short distance from it. The readings obtained at the new 
gauge proved that the surmise was correct, and the information was 
utilised by me when selecting a site for the first storage reservoir built 
on Table Mountain, viz., that known as the Wynberg Middle Eeservoir. 
The taking of readings of this gauge was not carried on regularly, and 
was discontinued altogether for a few months, but in May, 1892, two 
gauges were erected at other stations in the vicinity. Both of these 
places were nearer to the Disa Head gauge than the one originally 
adopted, the nearer station being only 500 yards and the further one 
1,300 yards away. 
Observations were taken of these gauges continuously from May, 
1892, to June, 1904. They showed that that neighbourhood received 
a larger rainfall than was indicated by the Disa Head gauge. Com- 
