From Devonshire Characters and Strange Events, Sabine Baring Gould
John Fitz was riding over the moor one day with his wife, when they lost their direction, were, in fact, pixy-led, and they floundered through bogs, and could nowhere hit on the packhorse track that led across the moors from Moreton Hampstead to Tavistock. Exhausted and parched with thirst they lighted on a crystal stream, dismounted, and drank copiously of the water. Not only were they refreshed, but at once John Fitz’s eyes were opened, the spell on him was undone, and he knew where he was and which direction he should take. Thereupon he raised his hand and vowed he would honour that well, so that such travellers as were pixy-led might drink at it and dispel the power over them exercised by the pixies. The spring still flows and rises under a granite structure erected in fulfilment of his vow by John Fitz; it bears his initials and the date 1568 in raised figures and letters on the covering stone. Formerly it was on a slope in the midst of moorland away from the main track, near the Blackabrook. Now it is enclosed in the reclaimed tract made into meadows by the convicts of Princetown. Happily the structure has not been destroyed: it is surrounded by a protecting wall.