It had a vital strategic placement on a rocky bluff over the St Lawrence River, at the furthest point that ocean-going ships could venture from the Atlantic.

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"This meant that the slates which were already being exported on a smaller scale from Blaenau Ffestiniog, could be loaded onto much bigger ocean-going ships inside a sheltered harbour... and of course in 1836 the railway is bringing slates down, " he said.

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By the time he reaches the other end and looks back, he feels more as if he were standing on a dock gazing up at the prow of a huge ocean-going vessel, perhaps one of Pessoa's dream ships.

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While oil does not damage ocean-going vessels, it will cling to their hulls, and it is illegal for ships to enter U.S. ports or waterways if they will contaminate the waters.

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