Although these machines are still a phenomenon of the virtual world, he believes that submicroscopic devices created from the manipulation of a very small number of atoms will someday change the world we live in. He took his case to Al Gore's Commerce, Science and Transportation Subcommittee on Science, Technology and Space on June 26 1992. Drexler's dream is of molecular machines that assemble themselves, make copies and then build other nanoscale machines, with various functionalities for everything from attacking individual diseased cells to creating a pork chop from kitchen waste by way of a molecular computer. The techniques used to build Nanoman and the bucky abacus, which involve manipulating individual atoms with macroscopic devices such as microscopes, will likely not provide the ultimate method of creating nanodevices, says Bruce Damer, a virtual reality expert at DigitalSpace Corporation in Santa Cruz, California. Hand tools are too clumsy to be an efficient means of creating nanodevices, despite the advances in control that have been made in the last ten years.
Many chemists favour supramolecular chemistry.
Julius Rebek Jr, now at the Scripps Research Institute in La Jolla, California, is designing small molecules that self replicate. Nobel prize winner Jean-Marie Lehn, at the Louis Pasteur University in Strasbourg, France, has developed numerous sensor molecules and chemical models that emulate enzymes, receptors and channels. Fraser Stoddart, now at Birmingham in the uk but soon to move to ucla in the usa, has built molecular scale switching devices. These and many other chemists are taking the first tentative steps towards molecular machines from the vantage point of the chemistry laboratory. Tying together these threads might eventually lead to working devices that can control, manipulate and process other atoms and molecules.