Mast cheeks
   The lower crosstree supports were the mast cheeks, strrong timbers, the same width as the trestletrees, which were fixed to the mast with hoops, bolts, and nails. On British ships from 1569 to 1720 the mast cheeks were fitted with sheaves over which the halyards reeved (see HALYARDS).

  The crosstrees
  The length of the main trestletrees was 0,3 to 0,35 of the width at the top of the main frame, the height 0,08 of the length, the width 0,9 of the height in the 16/17th centuries, reducing to 0.45 of the height by the  middle of the 18th century.
The crosstrees were as long as the trestletrees in the 16/17th centuries,  as broad in section, but only half the height, and let into trestletrees. In the 18th century the length of the crosstrees rose to 1,3 times the length of the trestletrees, they were then twice as broad in section, but still only half the height, and again let into them. The size of the crosstrees on the fore and mizen masts were in the same proportion to the main crosstrees as the masts were to each other. The topmast crosstrees were similar in design to the main tops, except that they were usually three in number to support the topgallant and royal shrouds. In their proportions they corresponded to of the lower masts.
    The topmast crosstrees were often curved aft slightly, and in the 16/17th centuries were the same length as the trestletrees, while by the middle of the 18th century they were sometimes almost twice
as long. In the 19th century spreaders were sometimes fitted to the
crosstrees over which the backstays ran. (see BACKSTAYS)All the crosstrees were fitted with wooden bolsters at the masthead,
which were rounded off on the outside edges; their purpose was to prevent the shrouds chafing on the edges of the trestletrees.

   The cap
   The purpose of the cap was to provide a support for the topmasts. There were two basic forms, an English form -which was widely adopted on the Continent after the middle of the 18th cenury – and a Continental one. In the 19th century caps were made of wood and there were no national differences.
   The length of the caps was 0,5 to 0,45 of the length of the masthead.
The rectangular hole fitted over the mast head cap tenon, and the round hole in front accepted the topmast heel. The holes and grooves in the Continental type of cap were designed to guide the halyards
(see HALYARDS). They disappeared at the beginning of the 18th century. The cap did retain its basic shape, but became considerably flatter, until it was completely superseded by the English type around the end of the century.
   In the 18th and early 19th centuries the caps were very often reinforced with iron bands. Until the middle of the 16th century the cap's front end was often just cut back to form a U-shaped recess. The  topmast was located in this recess, and fixed in place with a rope lashing round the cap.