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Each crosstree serves to spread another level of holding ropes on a fresh wider spar so as to provide support to the next mast top section. Effectively, the crosstree allows to extend the height, mount yet another layer of sail shrouds and option more wind power to the ships. The crosstree also
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The crosstree serves as a fresh base to spread the next level of supporting guy ropes, thereby providing a stable height extension to the masts. Without the crosstree, the ship's mast would have been severely limited in height, in relation to the beam of the ship.
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Any vertical structure like a mast is subject to dynamic swaying stress from wind, which levers immense force at the base of the mast. Such stress is countered through
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which are diagonally supporting ropes from mast top to its base. These ropes share the load on the mast tops and communicate that force to the base structure.
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so as to form an appropriate angular support against the sway the mast is exposed to, yet ships are fixed in their
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The taller the mast, the wider a base is required for the
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65:(if fitted). Similar transverse spars remain on
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