Six pictures by Cambridge painter Lewis Todd are being offered for sale at Ewbank Clarke Gammon Wellers in Woking, Surrey, on March 20. However, the greater interest in these works is what can be found on the reverse – the brushwork of Francis Bacon.

Bacon is known to have painted on the unprimed reverse of canvases and often mutilated anything with which he was not satisfied. These examples were apparently given to Todd by the manager of the Heffer Gallery in Cambridge, although it is not known how Bacon's used canvases came to be there in the first place.

Todd, who produced caricatures for the Cambridge Daily News, painted his own pictures on the front and then sold them at the city's All Saints Craft Market.

Five of these canvases have now been examined and authenticated by the Francis Bacon Authentication Committee and Ewbank's have estimated them at around £100,000 in all.

A sixth canvas from the same source is estimated at £5000-10,000, although, having recently returned from America, this has not been examined by the vetting committee.

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