William St Clair, 15th Baron of Roslin was the first
Hereditary Grandmaster of the
Scottish Order of Freemasons which was constituted to him by
charter. His elder brother, Edward, had conveyed to him the baronies of Roslin and
Herbertshire in 1582. He built the great
vaults and
turnpikes of
Roslin Castle. He also built one of the arches of the
drawbridge and the tower of the
dungeon. His initials appear in a stone dated 1596 which was when the work to the castle was finished. In 1601, he received a charter from Henry Saintcler the
Provost of Roslin for the church lands. In 1612, he resigned his lands lying within the
earldom of Caithness. ==Family==