control was becoming inadequate. A thorough check on all minor triangulation and control traverses in the Kowloon and New Kowloon areas was undertaken. An increased amount of levelling, both ordinary and precise, was also completed. Precise control surveys were carried out in connection with the alignment of the Cross Harbour Tunnel.
Mapping
7.18. The Branch's main effort is now directed at maintaining the new maps and plans in a reasonably up-to-date condition by a programme of systematic revision. As regards the large-scale plans, those covering rapidly developing (or re-developing) areas are being revised annually, others covering the main built-up areas at two-yearly intervals, while the sheets covering undeveloped and rural areas will be inspected and revised if necessary at three to five yearly intervals.
7.19. The first sheets of the 1:10,000 scale maps, which were received in 1968 and were based on field-completion in 1967, are already fast becoming out-dated in some areas and two of these (covering Kwai Chung and Kowloon) were revised during the year and will be re-printed as a second edition by the Survey Branch, Far East Land Forces.
7.20. The first sheet of a new bi-lingual edition of the 1:10,000 series was under preparation and the first 'pilot' sheet of this series will also be printed by the military Survey Branch. Arrangements will be made to print all future editions locally.
7.21. Of the 62 sheets of the 1:10,000 series which cover the whole Colony, a total of 51 sheets of the first edition had been published by the end of the year and bulk supplies of 48 sheets had been received and distributed to Government departments.
7.22. The first 8 sheets of the new 1:25,000 scale map, produced by the Directorate of Overseas Surveys, have been published and bulk supplies of 3 of these have been received and distributed to Government departments.
Title Survey
7.23. During the latter part of the year under review there was a significant increase in the demand for proposal plans, title surveys, etc. as a result of the renewed interest in land. There are signs that this
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