In many respects, the EM was not a great deal different from television, and in fact, the image was displayed on a television screen, a coated surface that glowed when electrons struck it. The great advantage of the electron microscope was that it could magnify objects far more than the light microscope. The reason for this had to do with quantum mechanics and the waveform theory of radiation. The best simple explanation had come from the electron microscopist Sidney Polton, also a racing enthusiast.

"Assume," Polton said, "that you have a road, with a sharp corner. Now assume that you have two automobiles, a sports car and a large truck. When the truck tries to go around the corner, it slips off the road; but the sports car manages it easily. Why? The sports car is lighter, and smaller, and faster; it is better suited to tight, sharp curves. On large, gentle curves, the automobiles will perform equally well, but on sharp curves, the sports car will do better.

"In the same way, an electron microscope will 'hold the road' better than a light microscope. All objects are made of corners, and edges. The electron wavelength is smaller than the quantum of light. It cuts the corners closer, follows the road better, and outlines it more precisely. With a light microscope—like a truck—you can follow only a large road. In microscopic terms this means only a large object, with large edges and gentle curves: cells, and nuclei. But an electron microscope can follow all the minor routes, the byroads, and can outline very small structures within the cell—mitochondria, ribosomes, membranes, reticula."

In actual practice there were several drawbacks to the electron microscope, which counterbalanced its great powers of magnification. For one thing, because it used electrons instead of light, the inside of the microscope had to be a vacuum. This meant it was impossible to examine living creatures.

But the most serious drawback had to do with the sections of specimen. These were extremely thin, making it difficult to get a good three-dimensional concept of the object under study.

Again, Polton had a simple analogy. "Let us say you cut an automobile in half down the middle. In that case, you could guess the complete, 'whole' structure. But if you cut a very thin slice from the automobile, and if you cut it on a strange angle, it could be more difficult. In your slice, you might have only a bit of bumper, and rubber tire, and glass. From such a slice, it would be hard to guess the shape and function of the full structure."

Stone was aware of all the drawbacks as he fitted the metal button into the EM, sealed it shut, and started the vacuum pump. He knew the drawbacks and he ignored them, because he had no choice. Limited as it was, the electron microscope was their only available high-power tool.

He turned down the room lights and clicked on the beam. He adjusted several dials to focus the beam. In a moment, the image came into focus, green and black on the screen.