A rare German M4 Enigma machine realised a world record $463,500 at Bonhams' History of Science and Technology sale in New York yesterday.

It beat the previous record, set at $350,000 for another M4 at Bonhams last year, by 32.4% - a result that indicates the rude health of the market.

The M4 Enigma machine caused trouble for the codebreakers at Bletchley Park

The Nazis used different versions of the Enigma machine for the various branches of the armed forces during the war.

The M4 machine was used by the navy - specifically the feared U-boat fleet, which caused havoc in the allied shipping lanes.

It threw the codebreakers at Bletchley Park when its transmissions first began to be intercepted in 1942, as it introduced an extra rota and a new set of codes into the mix.

Turing and team nicknamed it SHARK. It would be another nine months before they could break it.

Very few M4s have survived, as the majority were destroyed before captured U-boats could be breached.

Bonhams' science and technology expert Tom Lamb explained: "This M4 Enigma was in perfect condition and very desirable.

"Most of the 120 or so M4 Enigma machines known to have survived are in museums or in government hands so this was a rare chance to acquire one of the very few still available. I am, of course, delighted to have broken our own world record."

Alexander Fleming's original penicillin mould culture sold for $46,250.  

That's more than double its $20,000 high estimate.

The lot last sold at a Catherine Southon Auctioneers for £4,649 ($7,154) last year, resulting in an increase of 546.4%. That just goes to show the importance of picking the right sale.

Fleming first discovered penicillin's antibacterial properties in 1928, heralding one of the greatest medical breakthroughs of all time.