A NOTE ON THE TRIGONOMETRICAL SURVEY OF SOUTHERN RHODESIA

Abstract

After the completion of Simms's Geodetic Chain in 1901 and the publication of the results in 1905—Volume iii of the Geodetic Survey of South Africa—nothing further of a geodetic nature was done until 1928 when a short chain was run westwards from Simms's chain, at about latitude 17° 10′, to fix the Copper Queen mining area. The Eastern Circuit was commenced shortly after this; it runs from Salisbury eastwards to the Portuguese Boundary, southwards through Umtali to about latitude 20° and then westwards, joining Simms's chain again to the east of Bulawayo. Another chain running north from Simms's work has been commenced near Bulawayo. The several series are exhibited on the outline map attached.     

GEODETIC SIGNALS IN SOUTHERN RHODESIA

Abstract

So much has been written in the Empire Survey Review and other publications on the somewhat controversial subject of “Luminous or Opaque Signals in Geodetic and Primary Triangulation” that it may be of interest to give an outline of the types of signals used on such work in Southern Rhodesia, with particular reference to the completion of the Eastern Geodetic Circuit in 1935 and the type of signal that it has been decided to adopt for future work.     

REPORT OF THE SURVEY OF SOUTHERN RHODESIA FOR 1941

Abstract

1. General.—The size of this Report has been curtailed as far as possible in the interests of economy of reproduction and stationery. The usual annexures giving details of the work in the Drawing Office, the Lithographic Reproduction Press, and the Trigonometrical Survey have been relegated to the Departmental Records for use as required.     

DETERMINATION OF TAPE TEMPERATURES ON THE MEASUREMENT OF THE WANKIE AND SABI GEODETIC BASES,SOUTHERN RHODESIA (1953)

Abstract

The Wankie Geodetic Base was measured in May 1953 and the re-measurement of the Sabi Geodetic Base was also completed during the month following. For these measurements the standard “Macca” equipment was used, the gear being lent to the Southern Rhodesia Government by the Directorate of Colonial Surveys. As it was anticipated that both measurements would be made under hotter and more sunny conditions than normally prevail in England, the Directorate of Colonial Surveys suggested that the opportunity be taken of carrying out further tests in the determination of temperatures by the “resistance thermometer” as described by Messrs. Clark and Johnson of the National Physical Laboratory in their paper on the “Measurement of Temperature of Geodetic Surveying Tapes. Accordingly, through the good officesof the Director of the National Physical Laboratory, the apparatus comprising the resistance theremometer was made available for use on these two base measurements.     

THE TRANSVAAL-SOUTHERN RHODESIA GEODETIC CONNEXION

Abstract

In the original geodetic series in Southern Rhodesia—completed by Mr Alexander Simms in 1901—the geographical coordinates of all stations were referred to the point SALISBURYas origin. The coordinates of SALISBURY were fixed by interchange of telegraphic signals with the Royal Observatory at the Cape for longitude, combined with astronomical determinations of time, latitude, and azimuth (see Vol. III, “Geodetic Survey of South Africa”).     

THE GEODETIC SURVEY OF CANADA

Abstract

Shortly after the inception of the Geodetic Survey of Canada in 1905, reconnaissance for primary triangulation was commenced in the Ottawa-Montreal area. About the same time, precise levelliilg operations were begun from a bench mark already established by the United States Coast and Geodetic Survey near the International border at Rouses Point in Quebec.     

PROGRESS OF THE GEODETIC SURVEY OF NEWFOUNDLAND

Abstract

The third season (1937) of the Geodetic Survey of Newfoundland has now ended, the second in which angular measurements were made. Approximately half of the basic project has been finished, and two more seasons will leave little of it incomplete.     

NOTES ON GEODETIC WORK IN THE GOLD COAST

Abstract

The Gold Coast, including that portion of Togoland which is mandated to Great Britain, comprises an area of 91,843 square miles lying between the parallels 4° 45′ N. and 11°N. and the meridians 1° 10′ E. and 3° 10′ W. The greater part of the southern area is covered with dense forest, but in the north the forest gradually opens out to more open “orchard-bush”, while in the extreme north the country consists of rolling plains covered with tall elephant-grass.     

THE TRAINING OF AFRICANS FOR SURVEY IN NORTHERN RHODESIA

Abstract

Prior to the year 1931 there was no systematic training of Africans for land survey work in Northern Rhodesia, and those natives then in the employ of the Survey Department as assistants to the European surveyors in the field were no more than “capitaos”. Asurveyor, after his arrival in the colony, usually had to find his own native assistant, or chainman, and any native who appeared to have a commanding manner with his fellows, and who was clean and respectful, was eligible for the position. Preference in some cases was usually given to natives who had completed service in the native regiment or police, for their early training had taught them to obey orders, to conduct themselves well, and to control other natives.     

SURVEY CAMP: SOME NOTES ON THE MAKING OF LAND USE MAPS IN NATAL

Abstract

The duties of an Extension Officer of the South African Division of Soil Conservation and Extension are many and varied. Briefly, he gives professional advice on all aspects of farming (except veterinary), technical advice on engineering and building construction applied to farming, he does surveys and advises on dams, contour banks, etc., carries out stocks improvement and seed inspections, enforces the Weeds Act, and last but not least, sees to the enactment of the Soil Conservation Act. In these duties it is considered that one officer and two assistants are necessary for every 200 farms. Johnny Coles, B.Sc., with one full time, and occasional part-time, assistance has, as extension officer in the Ixopo district in Natal, over 1,000 farms comprising 1,800,000 acres, and a considerable number of government-owned properties in his care. Many men in his position would, in desperation over the hopelessness of the task, let things slide. Not so Johnny Coles who set about finding ways and means of getting the work done somehow.     

SIR DAVID GILL AND THE GEODETIC SURVEY OF SOUTH AFRICA AND THE ARC OF THE 30TH MERIDIAN

Abstract

In the memoir of the late Capt. G. T. McCaw which appeared in the January number of this Review (vii, 47,2), reference was made to the part which the late Sir David Gill played in the origin of the work on the survey of the Arc of the 30th Meridian in Africa. This year is the centenary of Gill's birth, as he was born in June 1843, and it is therefore timely to give some account of his work during his long term of office as Her Majesty's Astronomer at the Cape which resulted inthe inception and completion of the Geodetic Survey of South Africa and the survey of the Arc to the southern shores of Lake Tanganyika. He died on 24th January 1914.     

NOTES ON SURVEY APPARATUS AND INVENTION

Abstract

Age often approves and applauds the accomplishments of age. Not infrequently, however, the follower fails to affirm his faith in the faculties of his forerunner or, more definitely, if he has ever inquired into the matter, dismisses it with the common notion that these faculties are antiquated and therefore a questionable qualification. The heirs of all the ages are generally happy with their own mental equipment and give little credit to their inheritance. As a consequence they are prone to imagine that thoughts which darkly join in themselves are indubitably new contributions to their generation. A better acquaintance would often prove that some of these ideas are primordial and that, if further progress is to be made, an enlightened age must begin where a past generation has stopped—a truism not always recognized. It is in this sense that history can become really educative.