Which was the more important invention - the railway revolution ushered in by Stephenson's Rocket or the life-saving achievements of penicillin?
The Science Museum in London has chosen a top 10 list of its most significant objects, as part of events marking its centenary.
The public will be invited to vote on this list of scientific breakthroughs.
These "icons" of science will become part of a centenary trail for visitors to the South Kensington museum.
There have already been expressions of support for particular objects.
Trevor Baylis, the inventor, says he would vote for the V2 rocket engine.
SCIENCE MUSEUM TOP 10
V2 rocket engine
Model T Ford
Pilot ACE Computer
DNA double helix
Apollo 10 capsule
"It's one of the greatest achievements of our time because it led to space exploration, and then satellite development, which then led to mobile phones and the astounding communication services we enjoy today," he said.
Alice Roberts, television presenter and doctor, says she would vote for the invention of the X-ray machine.
"X-rays provided the first possibility of looking inside someone's body without cutting them open, a massive medical advance."
The museum's chief curator, Tim Boon, wants the top 10 to spark debate about the value of inventions and discoveries.
The hands of George V and Queen Mary in an X-ray
"What did we miss, is there an alternative top ten? Some of the objects may divide opinion. Would we be better off if some of the icons, which have had negative consequences, had not been invented?"
The Science Museum's origins lay in the Great Exhibition of 1851, with funds from the industrial showcase being used to begin a network of museums and libraries in South Kensington.
The first building, known as the South Kensington Museum, was opened to the public in 1857.
The centenary being celebrated this year is the creation in 1909 of a separately administered museum in a new building, which formally adopted the title "Science Museum".
For more information on the top ten visit the Science Museaum