Crosstrees

Crosstrees are the two horizontal spars at the upper ends of the topmasts of sailing ships that are used to anchor the shrouds from the topgallant mast.

Similar transverse spars remain on steamship and motor vessel masts to secure wire antennae or signal flag halyards.

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.

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.