"Tower of Glass" is a reference to a see through, reflective or hour glass shaped, allegorical tower of the Fisher King, that in fact existed at the Templar refuge in Nova Scotia.
The tower may have existed before 1398 and was reconstructed by Sinclair and his men with the aid of the Micmac Indians and was similar to the Newport and New Ross towers.
The relationship between the Westford Knight and the location of the "White" tower demonstrates that clues were left by Sinclair, albeit it in a sublime manner, indicating the exact location of the tower and the front and back door to an underground cave/ abandoned copper mine.
Also examined is the dismantling of the tower which was the temporary sanctuary of the holy relics and the subsequent hiding of the relics elsewhere.