LONG LINES ON THE EARTH : VARIOUS FORMULAE

Abstract

The use of radar has already begun to revolutionise the science of surveying. It requires the computation of lines on the earth between a hundred and a thousand miles long for the fixation of topographic control.     

THE UGANDA MAlLO SYSTEM

Abstract

The survey of “mailos” or native estates in the Kingdom of Buganda has taken a prominent place in the annual programme of the Survey Department of Uganda for over 30 years past. The survey, which has covered some 17,000 square miles and is now practically complete, has some unusual features, and although it has no claims to refinement or to great precision, a short account of its history and workings may be of general interest. The system of land settlement introduced by Sir Harry Johnston has already been described in the Empire Survey Review (“The Surveyor and the Politician”, by H. B. Thomas, vol. ii, p. 28).     

THE EARLY HYDROGRAPHIC SURVEYS OF THE BRITISH ISLES

Abstract

The 200th anniversary of the publication by Murdoch Mackenzie (Senior) in May 1750 of his “Orcades, or a Geographic and Hydrographic Survey of the Orkney and Lewis Islands, in 8 maps”, is an opportune moment for a brief résumé of the contribution made by Mackenzie and his successors in the field of nautical surveying. The appearance of this work ushered in a new era in marine survey, for it was the first charting carried out in this country based on a rigid triangulation framework. The importance of this fact can further be appreciated when it is remembered that a contemporary topographic map like General Roys' famous “Map of the Highlands” begun in 1747 was little more than an elaborate compass sketch; thus under Mackenzie's influence, marine surveying at this period was ahead of its topographic counterpart.     

SURVEYING INSTRUCTION AT THE UNIVERSITY

Abstract

The title and content of Mr. Ray's contribution to the July number of the E.S.R. entitled “Surveying Instruction at the University” is in the present writer's opinion, somewhat misleading. Obviously he is only referring to the teaching of surveying to civil engineering undergraduates and to students of such other branches of engineering as may be catered for, and does not mention the quite extensive surveying courses associated with the degrees in Geography and Mining at certain Universities. The gist of the article is confusing in that the author concludes by stating that he is “making an honest attempt to assess the merits of the surveying instruction given in the Universities of this country”, which is an admittedly worthy quest but scarcely compatible with some earlier statements such as “the long overdue overhaul of our University courses”, a statement which seems a little premature for one who is still in the stage of “honestly assessing” what is going on.     

Low-altitude geophysical magnetic prospecting based on multirotor UAV as a promising replacement for traditional ground survey

Abstract

The prospects for expanding the mineral resource base in many countries are linked with the exploration of stranded sites localized at unexplored areas with complex natural and landscape conditions that make any ground survey, including magnetic prospecting, difficult and expensive. The current level of geology requires high-precision and large-scale data at the first stages of geological exploration. Since 2012, technologies of aeromagnetic surveying with unmanned aircraft vehicles (UAV) enter the market, but most of them are based on big fixed-wing UAV and do not allow to substantially increase the level of survey granularity compared with traditional aerial methods. To increase the scale of survey, it is necessary to reduce the altitude and speed of flight, for which the authors develop the methodical and technical solutions described in this article. To obtain data at altitudes of 5 m above the terrain even in a rugged relief, we created heavy multirotor UAVs that are stable in flight and may be used in a wide range of environmental conditions (even a moderate snowfall), and develop a special software to generate flight missions on the basis of digital elevation models. A UAV has special design to reduce magnetic interference of the flight platform; the magnetic sensor is hung below the aircraft. This technology was conducted in a considerable amount of magnetic surveys in the mountainous regions of East Siberia between 2014 and 2016. The results of the comparison between airborne and ground surveys are presented, which show that the sensitivity of the developed system in conjunction with low-altitude measurements can cover any geologically significant anomalies of the magnetic field. An unmanned survey is cheaper and more productive; the multirotor-based technologies may largely replace traditional ground magnetic exploration in scales of 1:10,000?1:1000.     

THE SIERRA LEONE TOPOGRAPHICAL SURVEY

Abstract

The survey of Sierra Leone was fortunate enough to be completed just in time before the economic blizzard (if I may be permitted a well-worn journalistic cliché) descended on West Africa in common with the rest of the world and largely curtailed such activities. I do not propose to deal here with its technical side to any great extent. An excellent account of bush surveying is to be found in the “Handbook of the Southern Nigerian Survey”, which account always filled me with the greatest awe and respect for the men working there, their output being vastly greater than anything we were able to achieve in Sierra Leone. Truly “there were giants … in those days”.     

THE SEVEN-LENS AIR-SURVEY CAMERA

Abstract

Plate XIII shows an unrectified contact print taken from a negative. The leaves of the photographic rosette are so shaped that, after rectification, the resultant composite “vertical” shall be a perfect square, with all the gaps exactly closed.     

MODERN INFLUENCES ON THE UNIVERSITY ASPECT OF PROFESSIONAL TRAINING IN SURVEYING

Abstract

Surveying in, the sense in which I propose to consider it this evening, is the technical term given to the science of admeasuring and delineating the physical features of the earth and of works executed or proposed upon its surface. I am in some difficulty over a precise definition which will satisfy everyone since, although “surveying” is generally understood in the English language to have the above meaning, there is a growing tendency to use the somewhat restricted term” land survey"; restricted since it implies omission of hydrographic, hydrological and other forms of measurement of natural features and of setting out. This is, of course, not so.     

SOUTHERN RHODESIAN MILITARY SURVEYORS IN THE WORLD WAR, 1939–1945

Abstract

For some two months prior to the formation of the two companies, an intensive course of survey training and “refreshing” had been undergone by all ranks in the field sections, culminating in a combined Royal Artillery/Royal Engineer survey exercise from 1st to 10th October, carried out under operational conditions in all respects (even down to a 30-hour non-stop period of “photo-topo” compilation for the map on which the “final shoot” took place).     

TRAINING AFRICAN SURVEYORS IN UGANDA

Abstract

Under the Buganda Agreement, which was made in 1900 between the British Government and the Kabaka (King) of Buganda, approximately 9,000 square miles of the kingdom of Buganda were divided into numerous estates, which were allocated to the various reigning chiefs and people of importance at that time. The British Government agreed to survey these estates, most of which were one square mile in area; thus, the term “Mailo” as applied to the land owned by the Baganda, came into use. Since the original Mailo survey, which was completed in 1935, many of the estates have been subdivided. The land has been sold piecemeal, gifted and bequeathed, so that plots now exist which are even less than one acre in area and some in and near large townships are as small as half an acre. The task of the Survey Department is a gargantuan one and, in 1949, it was estimated that there were some 150,000 outstanding surveys.     

MINI-MACtm—A new generation dual—Band surveyor

Summary Litton Divisions presently produce both high accuracy GPS surveyors and low—cost GPS navigation sets. Aero Service'sMACROMETER ^R Interferometric Surveyors, have become the standard against which GPS surveying equipment is measured. Litton Aero Products has developed a highly digitized, low costL ₁,C/A code GPS card set. The integration of these technologies had led to the development of a low-cost, high-precision, GPS survey system which can be configured with or without a codelessL ₂ capability. TheMINI-MAC surveying system is the first member of the new generation of GPS survey systems resulting from this joint development. The system design is described in this paper, and initial survey test results using a prototypeMINI-MAC surveying system are presented.     

FIRST-ORDER TRAVERSES IN CEYLON

Abstract

In the last three years about 250 miles of “precise” traverse have been surveyed in this country to provide control for detail surveys. A brief account of the results may be of general interest. The traverses are situated where trig. points are far apart, and the cost of subsidiary triangulation would have been excessive on account of the flat nature of the country.     

RECOLLECTIONS OF A SURVEY OFFICER IN INDIA

Abstract

Crabs! Thousands of bright red crabs on a white foreshore; clinging black mud in tidal creeks with an overhanging tangle of tropical forest. These dominate one's memories of the Irrawaddy Delta in 1924. The Forest Department of Burma is the custodian of some 1,000 square miles of valuable forest reserves in the delta of this great river. The survey and production of “Forest” maps of this area was long overdue, postponed by reason of the immense expense and difficulty of a ground survey. Air survey, developed during the First World War, was ideally suited to this type of country but was still in its infancy, so that prolonged negotiations were necessary to persuade the Government of Burma to risk £25,000 on what appeared to them a doubtful proposition, as this was one of the first of the peace-time air surveys to be undertaken. Eventually, in July 1923 the contract was signed. Ronald Kemp, the first Chief Inspector of Civil Aircraft in India, gave up that post and formed an air survey company to carry out the photography as the first of his many survey contracts in India and Burma; I was in charge of the ground work and subsequent mapping.     

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.     

LIDAR Validation Using GIS: A Case Study Comparison between Two LIDAR Collection Methods

Abstract

In the summer of 2000, the Annapolis Valley of Nova Scotia, Canada was selected for a high‐resolution elevation survey utilizing LIDAR (Light Detection And Ranging). Two different LIDAR systems were used to acquire data for the area. The vertical accuracy specification for the survey called for heights to be within an average of 15 cm of measured GPS heights and 95% of the data to be within 30 cm. Prior to the application of these data to geoscientific problems, extensive validation procedures were employed. High precision GPS and traditional surveys were conducted to collect height validation checkpoints. Two validation methods were developed in a GIS environment that involved comparing the checkpoints to the original LIDAR points and to an interpolated “bald earth” DEM. A systematic height error between flight lines for one of the LIDAR methods was detected that related to the calibration procedures used in the survey. This study highlights the differences between laser systems, calibration and deployment methodologies and emphasizes the necessity for independent validation data.     

AERIAL PHOTOGRAPHIC STUDIES OF THE MARINE ECOLOGY OF THE WHITE SEA

Aerial photographic surveys of the White Sea have proven to be an effective means for studying the character of bottom relief and bottom sediments in shallow areas along its coast, particularly when film sensitive to visible radiation in the yellow-green range of the spectrum is used. More specifically, the article discusses methods of aerial photographic surveying, keys for the interpretation of different types of bottom sediments, methods of mapping underwater vegetation from air photos, and the potential of radar imagery for the indirect interpretation of bottom features. Sample interpretation maps from the White Sea are included. Translated by Edward Torrey, Alexandria, VA 22308 from Izvestiya Vsesoyuznogo Geograficheskogo Obshchestva, 1988, No. 4, pp. 314-321.     

SOME PROBLEMS OF RESECTION AND COUNTERSECTION-I

Abstract

“A Well-Defined mountain, though miles inland and never visited by the surveyors, will often prove the very keystone of a chart which cannot be regularly and theoretically triangulated” (“Hydrographic Surveying”, by Rear-Adm. Sir Wm J. L. Wharton, K.C.B., and Rear-Adm. Mostyn Field, F.R.S. 3rd Ed. 1909, p. 128). To many the reasons prohibiting the occupation of inland stations may be unknown; it may suffice to state that, in the past, British hydrographers have mapped many coastal waters where penetration of the land was at least inadvisable. Since the charts so made were in general sold to the world, seamen of all nations have benefited from the surveys.     

PRACTICAL APPLICATION OF THE LAPLACE LONGITUDE-AZIMUTH RELATION TO CONTROL OF GEODETIC ANOMALIES

Abstract

1. In geodetic work a ‘Laplace Point’ connotes a place where both longitude and azimuth have been observed astronomically. Geodetic surveys emanate from an “origin” O, whose coordinates are derived from astronomical observations: and positions of any other points embraced by the survey can be calculated on the basis of an assumed figure of reference which in practice is a spheroid formed by the revolution of an ellipse about its minor axis. The coordinates (latitude = ?, longitude = λ and azimuth = A) so computed are designated “geodetic”.     

LAND TENURE IN CANA

Abstract

The Dominion of Canada has an area of 3,695,189 sq. miles, nearly as large as the whole of Europe. It includes nine provinces, in six of which the cadastre (legal survey) has been laid down under different systems of survey, and only the remaining three under the comprehensive Dominion Lands System of Survey.