VVhen you haue berthed or brought her [the ship] vp to the planks, vvhich are thoſe thicke timbers vvhich goeth fore and aft on each ſide, vvhereon doth lie the beames of the firſt Orlop, vvhich is the firſt floore to ſupport the plankes doth couer the Hovvle, thoſe are great croſſe timbers, that keepes the ſhip ſides aſunder, the maine beame is euer next the maine maſt, […]
Source: wiktionary