MOS
particular technical and administrative functions of the Branch as a whole.
7.31
The functional work of the Branch is carried out by six main groups, namely, Control, Air Survey and Photogrammetric Unit, Mapping (including Site Surveys), Title, Training School and Cartography. Individual reports on the work carried out during the year are as follows :-
Control Survey
7.32
This work-group is primarily responsible for the provision and maintenance of the precise horizontal and vertical survey system on which nearly all other surveys are based.
7.33 A continuing problem is the removal or obstruction of survey stations particularly in developing areas such as the new towns. Steps are being taken to remedy the situation by providing Government Land Allocations for most of the triangulation stations, carrying out a programme of visiting and maintaining these stations and encouraging building consultants and the like to notify the Branch of possible disturbances to any survey stations.
7.34 The control survey done during the year included the routine work of providing horizontal and vertical control for mapping, engineering and other purposes, the checking of subsidence of certain buildings for Buildings Ordinance Office and the monitoring of building heights in support of the Hong Kong Airport (Control of Obstructions) Ordinance, Proposed 1977 Order.
7.35
The computer terminal in Murray Building continued to be used for various survey computations including aerial triangulation for the photogrammetric unit. However, access to the main computer remains a problem and delays ranging from a few hours to several days are common.
7.36
A Land Surveyor completed a three-months training attachment in U.K. on computing systems. The intention was to investigate the development in computing science as applied to land surveying with the object of setting up a suitable system for the Survey Branch, particularly its Photogrammetric Unit. His report is being studied.
Aerial Surveys
7.37
A total of 3,700 aerial photographs was taken during the year, a 40% increase over the previous year.
7.38
Demand for photography by a number of Government Departments continued to increase. Application of the photography was extended to cover many fields ranging from general pictorial appreciation to precise topographical mapping.
7.39 This year marked the first time the Branch was able to handle its own aerial survey in all respects, namely, the taking of photographs, the provision of ground control, the photogrammetric plotting and the fair drawing and reproduction of the resultant machine plots.
Photogrammetric Unit
7.40
This unit commenced work in February, 1976. However, it took some
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