SURVEYS AND MAPS 43 



join the fifth parallel about where it cuts the 27th meridian. Maury 

 (1934) has published a detailed account of all the triangulation in 

 the eastern part of the Congo. A large part of the Katanga has 

 been triangulated by the Service Geographique et Geologique du 

 Comite Special du Katanga. 



In Mozambique geodetic triangulation has been carried out on 

 the frontiers and in the Tete District, where 130,000 square kilo- 

 metres have been covered. This system has been carried along the 

 parallel of 15° South and connects with the main triangulation 

 chain of the Rhodesias. In Angola geodetic triangulations have 

 been carried along most of the boundaries by special commissions, 

 but in many areas framework for mapping depends on points 

 located by astronomical observations. Similarly in Portuguese 

 Guinea, geodetic work is limited to the frontiers. 



A correlation of triangulation in the Congo, Kenya, Uganda, 

 and Tanganyika by connection with short chains of triangles 

 would be desirable. The Uganda triangulation is based on a 

 small completed sector of the arc of the 30th meridian, and work in 

 Tanganyika will connect with the sector of this arc recently com- 

 pleted there, but correlation cannot be entirely satisfactory until 

 these two sectors are joined and a wider gap to the north of Uganda 

 is also filled. Therefore, the history of the triangulation of the 30th 

 arc and the possibilities of continuing it are summarized in the 

 following paragraphs based upon an Ordnance Survey Publication 



(1933). 



ARC OF 30th MERIDIAN 



Proceeding northwards from South Africa, the section of this 

 arc through Cape Province, Transvaal, and Southern Rhodesia 

 was completed at the beginning of the century under Sir David 

 Gill, and was continued in Northern Rhodesia in 1903-7 (results 

 published by the War Office in 1933). This work was resumed in 

 1 93 1 -3 and extended to the boundary between Tanganyika Terri- 

 tory and Ruanda-Urundi under Major Hotine, a distance of 402 

 miles at a cost of ;^i 7,000, funds being provided by the Northern 

 Rhodesian and Tanganyika Governments and the Colonial De- 

 velopment Fund. From here there is a gap in Ruanda-Urundi of 

 315 kilometres from 4° 20' S. to 1° 30' S., followed by a small strip 



