No, this is a widespread misunderstanding.The true story is as follows. Friedrich Engels lived in Manchester with his lover Mary Burns; his house backed onto the famous Manchester Ship Canal. In those days the canal was quite a pleasant spot, with grassy banks, fish and other wildlife including river birds in addition to the river traffic for which it had been built and the river folk who worked it. In other words there were many benefits to such a location, but also a few drawbacks; for example, some of the birds attracted to the canal had a habit of nesting in Engels's loft. Engels was expecting Karl Marx to visit him in Manchester; Marx wanted to get away from the noise and smoke of London and the busy routines of family life in order to concentrate on writing Das Kapital. The night before Marx was due to arrive, the Engels household had accommodated a rather rowdy party to which a number of the barge crews had been invited; as was usual among travelling folk, they came with a variety of musical instruments including several country fiddles, and made music until the small hours. They all crashed out on the bedroom floors, and to make room for so many bodies, Engels told them to stow their instruments in the loft. Marx arrived early next morning in a filthy temper. He'd been travelling all night in low company, had a splitting headache, and was not best pleased to find Engels's house strewn with unfamiliar sleeping bodies. He demanded a large pot of tea, so Engels went off to draw water for the kettle from the tap. But water came there none. Instead, there was a terrible knocking, flapping, and scraping in the loft, where the water cistern was located. Mary rushed upstairs to investigate, and came back shortly looking both embarrassed and amused.

"Well, Mary," asked Engels, "what's the matter? Has the water been cut off?"

"No, dear," Mary replied, "it's the violins and herons in the cistern."

Traditional