The New Year has begun, and between eating large amounts of Christmas cake and a small amount of alcohol, Greg and Jem have been preparing to face off in a debate over the greatest ever invention. It is time for the Smallpox Vaccine to go toe to toe with the Candle... After Greg sneaks in his first Houdini mention less than five minutes into the new year.

With both in a slightly whimsical mood, Jem has a 'what if' question about Batman, and Greg repeatedly forgets which war happened in the 40s!

Don't forget to let us know your candidates for the greatest invention,or anything else, at @condensedhist, @historygems or at condensedhistorygems@gmail.com.