82 
Transactions of the Royal Society of South Africa. 
Now the Lunar Calendar for the period under consideration is as 
C May 23, 0'17 a.m. 
The inference from this comparison seems now to be well established 
to the effect that — 
" The semi-diurnal fluctuations of level in Borehole No. V. attain a 
7naximum amplitude about the times of Neiu Moon and Full Moon, and 
attain a minimum amplitude about the times of the Moon's quadratures.'' 
A thermograph record of fluctuations of atmospheric temperature on 
the farm was also obtained for the fifteen weeks, but a comparison of these 
temperature curves with the water-level curves revealed no connection of 
any kind as existing between the two, and nothing further need be said of 
them. 
Comparison of Tarha Bridge Records luith South African Coastal Tide 
Gaitge Records. 
The elementary observations already described had shown the 
behaviour of Borehole No. V. to have an intimate relationship to the 
moon's position, and it now appeared advisable to compare the Tarka 
Bridge records with the coastal tide gauge records. 
For this purpose I selected the record for the fortnight June 4 to 
June 18 of 1905. My reasons for selecting this record were the 
following : — 
(a) This record was taken on the better machine of 1905. 
(b) It is a record on a large time scale over half an inch to the 
hour, and allows of greater accuracy in determining the times of 
successive high and low water in the semi-diurnal fluctuations. 
(c) It is the record for a fortnight in which little change of baro- 
metric pressure was recorded at Tarka Bridge, and thus the principal 
disturbing factor local to Tarka Bridge is nearly eliminated. 
follows : — 
1908. 
# March 2, 6.57 p.m. (Greenwich) • April 1, 5.2 a m. 
D March 9, 9.42 p.m. D April 8, 4.32 p.m. 
O March 18, 2.29 a.m. O April 16, 4.55 p.m. 
C March 25, 0.22 p.m. C April 23, 7.7 p.m. 
• April 30, 3.33 p.m. 
D May 8, 11.23 a.m. 
O May 16, 4.32 a.m. 
• May 30, 3.15 a.m. 
D June 7, 4.56 a.m. 
O June 14, 1.55 p.m. 
