(9) 
FUETHEE MAGNETIC OBSEEYATIONS IN SOUTH AFEICA. 
By J. C. Beattib, D.Sc, Professor of Physics, S.A. College, Cape Town. 
(Eeceived and Eead July 16, 1913.) 
During the years 1910-13 further magnetic observations have been 
carried out in South Africa with the view of extending our knowledge of 
the magnetic elements in those parts where as yet their values were 
unknown, and, in addition, to find the secular change of the magnetic 
elements in regions already surveyed." 
The parts of South Africa in which observations were made for the 
first time in this period were the West Transvaal, British Bechuanalandj 
and Bushmanland. In 1903 magnetic work had been carried on along 
the railways to the west and to the east of the East Transvaal, and in the 
summer 1910-11 further determinations were made in the country lying 
between the railways. A number of observations of the magnetic declina- 
tion had been carried out in these parts in 1909 by Mr. O. C. Macpherson 
during the course of a railway survey. The places at which observations 
were made for secular variation in this region were Klerksdorp (1911), 
Warrenton (1911-12), Mafeking (1911-12), Pretoria (1908). 
A number of observations was also made in the same summer in the 
eastern part of Cape Colony, two old stations (Alicedale Junction and 
Coerney) were reoccupied and four new ones established ; three of the 
latter were on the south and one to the north side of a magnetic ridge 
which had been approximately located by earlier work, f 
During the winter of 1911 repeat stations were occupied in the 
Eastern Province of the Cape, in the Eastern Transvaal, and in the 
Orange Free State. 
The observations in British Bechuanaland were carried out in the 
summer of 1911-12 ; the stations were distributed between the railway 
and the Kuruman Mountains ; only a few stations to the west of these 
mountains were occupied. In addition to the repeat stations, Warrenton 
and Mafeking, it was possible to occupy a station, Grootfontein, near where 
the declination was determined by Moorrees and Bosman in 1888. I 
In the winter of 1912 a number of repeat stations was occupied along 
the railway line from Matjesfontein to Biesjespoort ; in the same season 
three new stations were occupied in the Cape Province, and two in the 
Western Transvaal. 
* The work was supported by a grant-in-aid from the Union Government. 
t " Keport of a Magnetic Survey of South Africa," by J, C. Beattie, London, 1909, 
pages 92-93. 
X See " Report of a Magnetic Survey of South Africa," by J. C. Beattie, London, 1909. 
