The photo, probably the first of Keller and Sullivan together, also shows Keller holding a doll in her other hand. Significantly, 'doll' was the first word ever spoken by Keller. This would have been taught to her by Anne Sullivan, whose methods included spelling out words in the palm of Helen's hand.

The picture, taken at Cape Cod in July 1888, was found in an album by Thaxter Spencer, whose mother was a childhood friend of Keller. Mr Spencer donated the album and other items including diaries and letters to the genealogical society last June. However, the group did not notice the particular photograph until now.

Spencer admitted he had no idea how much of a stir the photograph would create, saying: "I never thought much about it. It just seemed like something no one would find very interesting."

"It's one of the best images I have seen in a long, long time," said Helen Selsdon, an archivist at the American Foundation for the Blind. "This is just a huge visual addition to the history of Helen and Annie."

About Helen Keller

Helen Adams Keller was born on 27 June 1880 in Tuscumbia, a small rural town in Northwest Alabama, USA. The daughter of Captain Arthur Henley Keller and Kate Adams Keller she was born with full sight and hearing.

Kate Keller was a tall, statuesque blond with blue eyes. She was some twenty years younger than her husband Captain Keller, a loyal southerner who had proudly served in the Confederate Army during the American Civil War.

The house they lived in was a simple, white, clapboard house built in 1820 by Helen’s grandparents. At the time of Helen’s birth the family were far from wealthy with Captain Keller earning a living as both a cotton plantation owner and the editor of a weekly local newspaper, the “North Alabamian”. Helen’s mother, as well as working on the plantation, would save money by making her own butter, lard, bacon and ham.

But Helen’s life was to change dramatically. In February 1882, when Helen was nineteen months old, she fell ill. To this day the nature of her ailment remains a mystery. The doctors of the time called it “brain fever”, whilst modern day doctors think it may have been scarlet fever or meningitis.

Whatever the illness, Helen was, for many days, expected to die. When, eventually, the fever subsided, Helen’s family rejoiced believing their daughter to be well again.

However, Helen’s mother soon noticed how her daughter was failing to respond when the dinner bell was rang or when she passed her hand in front of her daughter’s eyes.

It thus became apparent that Helen’s illness had left her both blind and deaf.

The following few years proved very hard for Helen and her family. Helen became a very difficult child, smashing dishes and lamps and terrorising the whole household with her screaming and temper tantrums. Relatives regarded her as a monster and thought she should be put into an institution.

By the time Helen was six her family had become desperate. Looking after Helen was proving too much for them. Kate Keller had read in Charles Dickens’ book “American Notes” of the fantastic work that had been done with another deaf and blind child, Laura Bridgman, and travelled to a specialist doctor in Baltimore for advice. They were given confirmation that Helen would never see or hear again but were told not to give up hope, the doctor believed Helen could be taught and he advised them to visit a local expert on the problems of deaf children. This expert was Alexander Graham Bell, the inventor of the telephone, Bell was now concentrating on what he considered his true vocation, the teaching of deaf children.

Alexander Graham Bell suggested that the Kellers write to Michael Anagnos, director of the Perkins Institution and Massachusetts Asylum for the Blind, and request that he try and find a teacher for Helen. Michael Anagnos considered Helen’s case and immediately recommended a former pupil of the institution, that woman was Anne Sullivan.

Read more about Helen Keller at the RNIB or at Wikipedia.