The image of a dust mite has a label ‘Silicon gear assembly’ and the text is titled ‘Building from the top down’ and reads: Gears are toothed disks that are designed to fit together so that the motion of one gear controls the motion of another. These silicon gears are among the smallest objects ever made from the top down. The text next to the image of a person made of atoms is titled ‘Building from the bottom up’ and reads: With a scanning tunnelling microscope, it is possible to move individual atoms or molecules. This figure, made of linked carbon monoxide molecules is just five nanometers tall. In 1990, scientists built this figure to demonstrate bottom-up construction methods. The image of nanogears has the labels of ‘Sheet of carbon atoms rolled into a tube’ and ‘Ring of carbon atoms with hydrogen atoms attachhed’. The text next to the image of nanogears is titled ‘Nanogears’ and reads as follows: This image of nanogears was produced with a computer program designed to make models of molecules. Hollow tubes called nanotubes made from sheets of carbon atoms do exist. So do the rings containing carbon and hydrogen atoms, which are used for the “teeth” of the gears. But researchers need to figure out how to get the “teeth”. The image of a part of a tunnel with particles inside has the label ‘Futuristic model of a nanorobot performing surgery in a blood vessel’ and is titled ‘The future of nanotechnology’. The text next to the image reads as follows: Potential applications for nanotechnology include medical diagnostic tools and atomic-level electronic devices that assemble themselves. If such devices prove successful, perhaps someday the surgical robot will be built.