| 摘要 |
A lowerable mast comprising first and second sections, the first section being anchorable at one end in an anchoring position, the second section being pivotally connected intermediate its ends to the first section by a pivotal interconnection with portion of its one end in overlapping relationship with at least portion of the first section in any of its pivotal positions, opposed inwardly directed faces of the overlapping regions of the first and second sections providing sliding co-operative faces for supporting the second section relative to the first section.
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