280. Compressed air at Tsat Tze Mui is supplied by two "Broomwade" Type EH 330 cubic feet per minute twin cylinder stationary compressors, working together, and at Hok Un by two Broomwade Type E 600 cubic feet per minute 4-cylinder compressors working alternately. Extensive overhauls and replacement of parts were carried out on these latter machines which have now given many years service. Increasing output from both quarries made it necessary to install a portable 210 cubic feet per minute compressor at each to supplement supply from the stationary machines.
281. Demands for stone continued to make it necessary for both quarries to work 16 hours a day, 6 days a week, throughout the year.
Total output of crushed stone for the first time exceeded 200,000 tons, the actual increase over the previous year's production being 14.5%.
282. The following table shows the output from the Quarries in comparison with the figures for the four previous years.
Quarry Crushed Stone (Tons) Bitumen Macadam (Tons) 50/51 51/52 52/53 53/54 54/55 50/51 51/52 52/53 53/54 54/55 Hok Un 46,776 60,203 92,521 84,980 105,331 32,233 22,885 23,656 26,938 25,107 Morrison Hill (a) 29,887 11,626 Hung Shui Kiu (b) 6,670 2,229 Tsat Tze Mui 29,506 88,646 97,383 103,457 (c) 10,537 25,339 21,326 24,826 Total 53,446 91,938 181,167 182,363 208,788 62,120 45,048 48,995 48,264 49,933(a) Closed down in September 1951. Quarry was operated by contract, mixing plant only operated by Roads Office.
(b) Closed down in August, 1951.
(c) Started full production in September 1951.
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