The family of former Keighley MP Sir Marcus Worsley is auctioning off paintings by the 18th century watercolourist Francis Towne.

Sir Marcus's father, the late Sir William Worsley (1890-1973), bought and owned the paintings for just £2,000. They are now expected to fetch up to £368,000.

Sir William left the Towne painting legacy to his family, and some are due to be auctioned at Christie's, in London, on June 5.

Landowner Sir Marcus Worsley, 78, is the duchess of Kent's brother and was Conservative MP for Keighley between 1959 and 1964.

His father, the late Sir William Worsley, was one of the leading collectors of English watercolours of the immediate post war period.

Between 1944 and 1960 Sir William collected art by Francis Towne (1739-1816), eventually owning 36 works covering every period of Towne's career.

The 14 lots up for auction are expected to make a healthy profit on what Sir William paid for them.

One picture alone (pictured above) -- Waterfall between Chiavenna and Mount Splugen, Switzerland -- which cost Sir William about £360, is expected to be sold for £100,000.

A picture of the town of Lugano, Switzerland, seen from the paradiso with the church of Santa Maria degli Angeli, Church of Loreto, the Cathedral of San Lorenzo, the Municipality, the Casa Airoldi and the Gargantini Buildings, was bought by Sir William for £80 and is now valued at up to £60,000.

In January 1950, Sir William provided an entire exhibition of works by Towne to the city art gallery in York, the first ever to be held in a public gallery.

Sir William's collection covers every aspect of Towne's career from early conventional views of Devon, through to the tours to Wales in 1777, Italy and Switzerland in 1780-81 and the Lake District in 1786.

Francis Towne was a landscape painter whose idiosyncratic style relied on economic and careful pen outlines and flat muted washes of colour.

Sir William did not shy away from unusual or untypical examples, and had a genuine enthusiasm for Towne's work. He maintained close contact with another collector, Paul Oppe -- probably his only serious rival as a collector of Towne's work.

His letters to Oppe told of his delight as he reunited groups of drawings which had been sold to different sources and separated.