Nanotechnology, or molecular manufacturing, is the precise manipulation of individual atoms or groups of atoms by mechanical means. The term nanotechnology comes from the nanometer ( 10 ^{- 9} meter) scale at which the devices work. The concept of working at the atomic scale is not new. Richard Feynman gave a talk in 1959 about the possibilities of a physicist being able to precisely position atoms as requested by a chemist. As technology and understanding increased, the manipulation of individual atoms became possible. Several years ago, researchers at IBM managed to spell out the company name using individual xenon atoms without any bonds to hold them in place (the name only lasted about five minutes before the atoms wandered off).

Twenty years after Feynman had proposed precise molecular manipulation, Drexler published a paper on the subject in the Proceedings of the National Academy of Sciences. Later, in the mid-1980s, he wrote a book on nanotechnology called Engines of creation [1] to spread the idea to the general public and begin public discussions on a technology with far-ranging life-and-death potential. The book grabbed the imaginations of many people (myself included) with its scenarios both of wealth and long, healthy lives and of ultimate disaster for the biosphere, with its depiction of the potential use and abuse of a technology able to build molecules like Tinker-toys.

In this volume, Drexler presents the technical analysis of molecular machinery and manufacturing. The book is divided into three parts that start at the atomic scale and work up to devices containing tens of thousands of atoms. The chapters in the first part are full of equations and charts describing how atoms and molecules interact. The first part takes up about half of the book. It contains the foundation and basis for Drexler’s proposals and is where more of the objections to this new field can be logically tested.

The second part describes various devices and systems based on the framework built in the first section. We are shown diagrams of rods, cams, and bearings, many designed in atomic detail and analyzed using standard modeling techniques drawn from computational chemistry. Equations and charts back up these molecular machines. Using the basic parts described in the early chapters, molecular factories and computers are sketched out. This material is similar to the description of devices in the nineteenth century that drove the industrial revolution, but these machines could fit into one of your body’s cells instead of a large building. The chapter on mechanical computing would probably be the most comprehensible to those with a computing background. How would you like a 1000 MIPS computer that would fit into a cubic micrometer and draw 0.1 microwatt?

The final part deals with how to approach making these devices. Drexler discusses three different possible approaches: biological, chemical, and physical. The biological approach uses proteins as components for first-generation molecular machines. The chemical approach uses a more traditional approach to creating molecular building blocks with various reactions and catalysts. The physical approach would use an atomic force microscope to physically touch molecules and atoms. By touching, the shape of molecules could be determined and atoms or molecules could be precisely placed.

The book has two appendices. One discusses the issues and philosophy of this recently defined field, and the other describes progress in related fields. Drexler describes nanotechnology as a branch of “theoretical” applied science, meaning that the nanomechanisms can be explored and defined from a base of scientific knowledge and understanding of engineered devices, but, alas, nothing can be built for perhaps the next 10 to 15 years. This book should go a long way in answering some of the technical criticisms of nanotechnology. It will probably see use in graduate studies and as a reference work for many years.

Most of this book assumes readers have a strong chemical or physics background, but it has an excellent glossary and symbols listing to help those who do not. By skipping most of Part 1, readers can avoid most of the chemistry and physics and enjoy the fascinating mechanical devices made up of a few thousand atoms or fewer. For people who just want a general introduction, I would recommend Drexler’s two earlier books [1,2]. Although Engines of creation is already dated and contains several flaws that Drexler has pointed out, it gives food for thought on what the twenty-first century could hold. Drexler also gives an address, phone numbers, and an electronic mail address for the Foresight Institute, which he founded to help guide and promote research into nanotechnologies, for those who want to keep up with developments on the frontier of a new field.