For two decades it was the Edinburgh vessel that ran like clockwork - despite repeatedly losing its cargo at sea.
Aptly taking its name from the infamous warning call from the days when the contents of Edinburgh's chamber pots would be ejected from open windows, the MV Gardyloo made thousands of voyages out to the North Sea to dispose of the capital's sewage.
It's hard to imagine now, but, up until fairly recently, the practice of dumping vast quantities of our poo and pee at sea was perfectly legal in spite of the obvious environmental hazard it posed to marine life.
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Starting in 1978, the sludge ship would leave its berth at Leith Docks around two-to-three times a week and sail out to one of two designated spots to release its toxic load.
The two dumping grounds were allocated by the Department of Agriculture and Fisheries. In the summer months, the vessel would make for a spot close to the Bell Rock, 12 miles east of Dundee, while during the winter the destination was off the coast of St Abbs, Berwickshire.
Both journeys were round trips of approximately seven hours, with the disposal phase taking around 20 minutes.
Intriguingly, ordinary passengers could also join the Gardyloo on its dumping trips. In April 1978, a group of eight ladies from Livingston would be the first of more than 6,000 passengers to board the vessel over the next 20 years.
While admitting his may not be the "most glamorous" job in the world, MV Gardyloo Chief Officer Ronald Leask quipped: "But I've had worse cargoes - and some of them were human!"
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MV Gardyloo's tenure at Leith was brought to an end in 1998, when a new EU waste water treatment directive banned the dumping of human waste at sea. From then on, waste from the Seafield sewage plant would be sent to landfill.
In two decades, the Gardyloo made a total of 2,600 voyages, dumping an estimated 8.5 million tonnes of sewage.
But that would not be the end of the Port Glasgow-built vessel.
After a spell being laid up at Hull, MV Gardyloo was sold on three times over the next few years to different UK companies.
Then, in 2004, the ship was bought by the state shipping enterprise, the Azerbaijan Caspian Shipping Company.
Since renamed Shollar, the former Gardyloo is now berthed at the Caspian Sea port of Baku - a full 3,000 miles away from sunny Leith and the North Sea.
And Shollar is no carrier of human waste - quite the opposite.
The vessel is a water carrier and named after the Azerbaijani Shollar water, from the Shollar spring in the Caucasus Mountain range. Fresh water is piped from here and distributed to the entire region, quenching the thirst of millions.
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