First year since 1963-64 no survey work for air photo control was required and the final batch of machine-plots at large scales was received from the contractor for field-checking. All the plotted sheets of the 1/10,000 series of maps had also been field-completed by the end of the year and a total of 49 sheets had been printed. Bulk supplies of most of these were received and distributed to Government departments. (For Survey Branch statistics see Appendix V).
7.15. The difficulty in recruiting professional staff and the increase in the number of posts for Land Surveyor/Assistant Land Surveyor in the Civil Engineering and Highways Offices resulted in as many as 7 vacancies in a total of 17 posts at the end of 1969. One of these has been filled by the transfer of an Engineer and another by the appointment to Assistant Land Surveyor of a Surveying Assistant (Land), Class II who had completed his professional training in United Kingdom.
7.16. The work of the Branch is undertaken by two Divisions, namely Hong Kong and Islands Survey, and Mainland Survey. Functionally, the task of the branch is divided into four main categories:
(a) Control Survey. The provision of the rigid framework of fixed points, on both horizontal and vertical planes, on which all surveys are based, viz. triangulation stations; picket-boxes; traverse stations and level datum bench marks.
(b) Mapping Survey. Surveys for the preparation of plans and maps of the whole Colony at different scales and their subsequent revision at regular intervals.
(c) Title Survey. The delineation and recording of all property boundaries in the urban areas (and in planned areas of the New Territories); the implementation of all town planning layouts; surveys for surrenders, grants, sales, exchanges, Crown Leases, etc.
(d) Cartography. The production of plans and maps at different scales for both 'Mapping' and 'Title' purposes.
Control Survey
7.17. Since no ground control surveys for aerial survey were required during the year a greater effort could be made to establish rigid traverse control in the urban areas. A very high proportion of the ground marks have disappeared in the past few years and the general framework of
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