The picture titled: "Gypsy Life – The Hop Pickers" (pictured above) is by the outstanding Royal Academician Sir Alfred Munnings (1878-1959), who is also now acknowledged as one of Britain's greatest-ever horse painters.
Munnings was first introduced to gypsies by his friend Olive Branson, who had a house in Hampshire.
Each autumn, gypsies would congregate at Binsted for the hop-picking season and Munnings visited Hampshire for the first time in 1913,
He later recalled: "Of all my painting experiences none was so alluring and colourful as those visits spent amongst the gypsy hop-pickers in Hampshire each September.
"More glamour and excitement were packed into those six weeks than a painter could well contend with. I still have a vision of brown faces, black hair, ear-rings, black hats and black skirts; of lithe figures of women and children, of men with lurcher dogs and horses of all kinds... Never in my life have I been so filled with a desire to work as I was then."
The Binsted painting coming up for sale was included in Munnings's 1920 exhibition, Gypsies in Hampshire, at the Connell Brothers's Bond Street gallery.
According to Christie's: "This exhibition was to prove a landmark in Munnings's career as it brought him his first significant financial and critical success."
Munnings – like Constable, he was a Suffolk miller's son – was an extraordinary figure.
When he was 20 he lost the sight of his right eye in an accident ( a blow from a briar when he lifted a dog over a hedge) yet despite this handicap he rose to become, on December 11, 1944, president of the Royal Academy, which confirmed his position as one of the most distinguished artists of his time.
Munnings started his working life as a 2s 6d (12 1/2p) a week apprentice lithographer with a Norwich firm, Page Brothers.
Now interest in and the value of Munnings's art is soaring. Last June, at Sotheby's in New York, his painting "Saddling Mahmoud, the Derby Winner 1936" fetched £2,546,502.