Poor guy 
Nevertheless, the 86-year-old was determined to finish his five-foot long, 5,000-piece jigsaw.
And when he thought the painstaking process was complete, he stood back to admire his work - only to find a dog may have eaten the final piece.
Incomplete: Pensioner Jack Harris with the jigsaw which has one piece missing
Mr Harris has searched his home in Shepton Mallet, Somerset, for the missing piece but his family fears one of their two dogs has swallowed it.
They have even asked the puzzle's manufacturer if they could provide a spare - but Mr Harris has taken so long to complete the jigsaw that Falcon Games has stopped making it.
His daughter-in-law Eve Harris, who gave him the jigsaw as a Christmas present in 2002, said she thought it would be a challenge for the retired businessman.
Mr Harris, whose wife Doris died in 2004, is given a new jigsaw every year, and usually finishes them by spring.
But this puzzle was to prove different.
He said he started the jigsaw - which shows the 19th century oil painting The Return Of The Prodigal Son, by James Tissot - as usual. But eight years later he was still struggling to finish it.
Mrs Harris said: 'We got him this one as a bit of a joke really, because he always boasted he could get them done so quickly, he's a bit of a whiz with them.
In bits: Close up of the missing piece of Jack Harris' 5000 piece jigsaw which he started seven and a half years ago
'It was marvellous to see it finally completed. But when we saw there was a piece missing from the middle, we just couldn't believe it.
'He was just so disappointed when he found one bit was missing. It's sad really because now it will never be completed.'
If Mrs Harris's dogs are not to blame, the family think the piece may have been thrown away by accident.
Mr Harris said: 'I always said I could get the puzzles done by the end of March so I could get out into the garden, but this one took a bit longer.'
Nevertheless, the 86-year-old was determined to finish his five-foot long, 5,000-piece jigsaw.
And when he thought the painstaking process was complete, he stood back to admire his work - only to find a dog may have eaten the final piece.
Incomplete: Pensioner Jack Harris with the jigsaw which has one piece missing Mr Harris has searched his home in Shepton Mallet, Somerset, for the missing piece but his family fears one of their two dogs has swallowed it.
They have even asked the puzzle's manufacturer if they could provide a spare - but Mr Harris has taken so long to complete the jigsaw that Falcon Games has stopped making it.
His daughter-in-law Eve Harris, who gave him the jigsaw as a Christmas present in 2002, said she thought it would be a challenge for the retired businessman.
Mr Harris, whose wife Doris died in 2004, is given a new jigsaw every year, and usually finishes them by spring.
But this puzzle was to prove different.
He said he started the jigsaw - which shows the 19th century oil painting The Return Of The Prodigal Son, by James Tissot - as usual. But eight years later he was still struggling to finish it.
Mrs Harris said: 'We got him this one as a bit of a joke really, because he always boasted he could get them done so quickly, he's a bit of a whiz with them.
In bits: Close up of the missing piece of Jack Harris' 5000 piece jigsaw which he started seven and a half years ago
'It was marvellous to see it finally completed. But when we saw there was a piece missing from the middle, we just couldn't believe it.
'He was just so disappointed when he found one bit was missing. It's sad really because now it will never be completed.'
If Mrs Harris's dogs are not to blame, the family think the piece may have been thrown away by accident.
Mr Harris said: 'I always said I could get the puzzles done by the end of March so I could get out into the garden, but this one took a bit longer.'
