182 Transactions of the Boyal Society of South Africa. 
The values of the magnetic elements are given in the list which 
follows ; further details of the observations at these stations, the position 
of the stations, the instruments used, and other facts will be found in one or 
other of the following publications. The number given immediately after 
the name of the station in Appendix I. refers to these publications. 
1. "The Magnetic Elements at the Cape of Good Hope from 1605 
to 1900." By J. C. Beattie and J. T. Morrison. Trans. S.A. 
Philosophical Society, vol. xiv., p. 1. Cape Town, 1903. 
2. Eeport of a Magnetic Survey of South Africa." By J. C. Beattie. 
Eoyal Society. London, 1909. 
3. "On Magnetic Work in Southern and Central Africa." By J. C. 
Beattie and J. T. Morrison. Washington, 1913. 
4. " Further Magnetic Observations in South Africa." By J. C. 
Beattie. Trans. Eoyal Society of South Africa, vol. iv., p. 9. 
Cape Town, 1914. 
5. " Bulletin de I'instifcut oceanographique. Contribution aux etudes de 
magnetisme terrestre en Afrique." Par F. A. Chaves. Monaco, 
1908. 
6. " Eeport on the Eesults of a Magnetic Survey of the Clanwilliam, 
Van Ehynsdorp, and Calvinia Districts." By J. C. Beattie. 
Eeport of the South African Association for the Advancement 
of Science. Cape Town, 1909. 
7. Appendix to present paper. 
8. " Veroffentlichungen des hydrographischen Amtes der K. und K. 
Kriegs-Marine in Pola." Gruppe IV. Erdmagnetische Eeise- 
beobachtungen III Heft. Pola, 1902. 
9. " Magnetic Observations in Northern Africa." By B, F. E. Keeling. 
Cairo, 1907. 
The results for the declination are shown in Plate I., where the lines 
of equal annual change have been drawn. The only results not given 
in the preceding list are, first, the secular change determined from the 
Gauss-Carnegie observations (" Terrestrial Magnetism," vol. xvi., p. 136), 
and secondly, the change given for the Katanga district of the Congo, a 
result determined from a comparison of Beattie and Morrison's observa- 
tions in Northern Ehodesia in 1909 and Lemaire's in the Congo in 1899 
and 1900. It will be noticed that the lines of annual change have been 
closed so as to show a centre of high annual decrease on the east coast of 
the mainland and extending into the neighbouring ocean ; the only justifi- 
cation for the latter is the analogy with the results shown on the British 
and American magnetic charts. A comparison of the map for the main- 
land given here with the charts shows no continuity between the land and 
the sea curves, nor does the extraordinarily high value over the land find 
any analogue on the sea except in the case of the result obtained from the 
