Auctioneer Andrew Stowe said: “These two marbles changed not only the course of the war but the entire world as we know it.
“They may be small, but their importance is gigantic.
”These marbles were once just children’s toys, but they played a pivotal role in the design of the “bouncing bomb.”
”Without these marbles, the famous Dam Buster raids would not have happened, and the outcome of the war could have been very different.
”They are the most important marbles in the world. Over fifteen thousand pounds for these two marbles is an incredible result.
”There were over twenty bidders from five different countries, and they attracted close to one-hundred bids.”
In 2020 a letter to Barnes Wallis from his daughter recalling how they practiced it with marbles went on sale.

The excited note from “Wiggy” to her daddy shed more light on how he came up the ‘Bouncing Bomb’.
He first proposed the famous weapon in a paper published in 1942 before it was deployed a year later.
Wiggy – Mary Wallis, then 16 – penned a congratulatory note to her father just three days after the second night of bombing in 1943.
It listed a number of experiments the family carried out – including the “impossible task of trying to see whether a minute marble bounced under or over a wobbly piece of string”.
Signed ‘Wiggy’, a family nickname, and dated May 20, it begins: “Hooray, horray, hooray!!! Wonderful marbles. Up the marbles. Cheers cheers cheers!”
The idea behind the bouncing bomb was a weapon that could skip over the surface of water and avoid torpedo nets before sinking next to its target.
The explosion would then act like a depth charge – concentrating the force of the surrounding water.
Barnes, hailed as a war hero for his efforts towards the bouncing bomb, died in 1979. Mary passed away in 2019.
Produced in association with SWNS Talker