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Owen wanted his niece to see the gap between moving an atom and building an object . She had heard the phrase molecular manufacturing and pictured a small factory setting each molecule where a plan told it to go . Eric Drexler had put that picture in front of the public in the 1980s . Owen had one photograph that looked , at first , like proof . In 1990 , at IBM , two researchers used a scanning tunneling microscope to slide xenon atoms across a nickel surface . The surface was under vacuum , and cold enough that an atom stayed where the tip left it . When they finished , the atoms spelled IBM . The work is one tip , then the next atom , and it is slow . A line that produced even a simple device would need a huge number of those steps , running together , in conditions a workshop can keep . The photograph does not contain that line . Beside it he put a quieter kind of nanoscale assembly . Paul Rothemund showed how to fold one long strand of DNA into a chosen flat shape with many short staple strands . The pairs follow Watson and Crick : each base finds its partner , so the sequence is a set of instructions . The same idea has since made small cages . Here DNA is a scaffold . Its job is to hold another molecule in a chosen place , not to carry a bridge . A click reaction sits closer to the staples than to the tip . It is chosen because it joins the pieces you meant to join , among a crowd of molecules at once . None of this is the factory Drexler described . It is more control than cutting and pouring a bulk material , and less than a plan that names every atom . She asked whether a protein could stand in the middle . Inside a cell , a protein already can cut , carry , or pull . People can change its sequence , and they still build with the twenty common amino acids . Take many of those machines out of that wet , crowded interior and they lose the shape that lets them work . A neat fold in a tube is not a workshop . At the door she tapped a line about graphene , carbon in a sheet one atom thick . Owen said that sheets like that , and some crystals grown a layer at a time by molecular beam epitaxy , are real control of matter . They still do not pick up one molecule and set it into a finished product . He slid the photograph into its sleeve . The letters showed that a tip can park an atom . They did not hand her an object she could carry home .
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