Scope and Contents Vocabulary note written down by John Ewen MacRury, Beinn na Faoghla/Benbecula entitled 'Clach Nathrach' describing it as an 'accumulation of liquid matter form the mouth of the serpent' and where and how it is formed. He recalls having seeing a clach nathrach when at school in Uig, Lewis which was found by 'the herd boy of Croulista...on the south side of Suanaval hill' [Suaineabhal, Eilean Leòdhais/Isle of Lewis]. MacRury notes the clach nathrach as being valued for its healing properties...