This pattern is that from D C Stewart's 'Setts of the Scottish Tartans'. It also appears in his father's book 'Old & Rare Scottish Tartans'. DCW said this was in existence in 1812 prior to the Ogilvies and the Drummonds of Strathallan becoming connected through marriage. A strange - and so far inexplicable - fact that he pointed out was that the complicated Drummond of Strathallan contains many elements from this Ogilivy tartan - as if forecasting the 1812 wedding.