The wooden schooner John Preston was launched at Bangor, Wales in 1855. She measured 76.3′ x 19.5′ x 11.7′ and she was 126 registered tons. Built for Mr E Williams, Port Dinorwic she was registered in Caernarvon.
On 12th December 1882 she was en route from Port Dinorwic in Wales to Fraserburgh with a cargo of slates when she was caught in a severe gale. Her skipper, W Jones, decided to take refuge in the sheltered waters of the Sound of Mull to ride out the storm. She anchored in Scallcastle Bay but unfortunately, even in the lee of Mull she was battered by strong winds and a large swell which finally caused her anchor line to give way. She was swept helpless across the Sound of Mull and onto the shoreline west of Lochaline where she was to become a total wreck. All six crewmen made it safely to shore before the ship went down.
The remains of the John Preston lie precariously on a sand/shingle ledge at the top of a dramatic underwater cliff in position 56° 31.983’N, 005° 48.198’W. The site is approximately half a mile west of Lochaline Pier. Between the pier and the site a spectacular underwater cliff lies only a few metres from the shore dropping to depths well in excess of 50 metres. The wreck itself, as you would expect, has almost entirely disappeared but the remains of the cargo, piles and piles of slates, are still scattered across the seabed giving the wreck its local nickname – The Slate Wreck. There is still one large piece of wooden hull remaining and many bits and pieces of metallic structure scattered around.
The wreck lies in depths from 14 – 16 metres. The wreckage reaches to the edge of the cliff which then plunges below into the darkness. The site is generally sheltered from the worst of the currents in the Sound but is subject to gentle tidal flows which make a drift along the cliff face and excellent way to complete the exploration of the wreck.