The food industry has begun to experiment with irradiation as a new way to sterilize food. Items which normally spoil quickly, such as hamburger, sausage, cheese, and bread, are exposed to radiation. The rays destroy all of the bacteria that cause food to spoil. The food is immediately sealed in airtight plastic bags. It will remain perfectly fresh for months--or even years. This process may make the canning or freezing of food completely unnecessary. [Illustration] [Illustration] Even foods which generally keep well, such as onions or potatoes, can be helped by irradiation. The treatment kills any insects that might be in the sack, and also keeps the vegetables from sprouting. A treated potato will keep for a very long time. A number of experiments have been done with potatoes. Before long you will probably see irradiated potatoes for sale in your market. Irradiation can even improve food crops and other plants while they are still being grown. Changes caused by the rays have already created new and better varieties of corn, peanuts, and oats. The same dose of irradiation works in another way, too--it kills the insects which damage the crops. Irradiation used in certain medicines can destroy a patient's diseased tissue. Many forms of cancer are treated by this method. In some cases, the patient is injected with a radioisotope. In other cases, he is just exposed to its rays, which are projected from a special machine. Sometimes, tiny bits of isotope, called _seeds_, are actually placed directly in the cancer. Other patients are asked to drink the isotope in a special preparation called a "radioactive cocktail." [Illustration] Besides their many uses as tracers and irradiators, isotopes have great value as substitutes for expensive X-ray machines. The rays can pass through many materials and, by making a picture on a film underneath, can show differences in thickness or other flaws. Some of the materials that are inspected this way are sheet metal, paper, rubber, and plastics. Also, piston rings for auto engines, and airplane engine valves. Doctors, too, can use radioisotopes instead of X rays. An X-ray machine is a huge piece of equipment which needs a special room and costs thousands of dollars. A radioisotope machine is about the size of a large can of fruit juice and weighs only ten pounds. It can be carried about easily and is most valuable in an emergency or at a place where there is no X ray available. These are only some of the things that atoms can do for us. Atomic energy is still young. In the years to come, there will be many changes. During your lifetime, the peaceful atom should make the world an easier, healthier, happier place! [Illustration] APPENDIX Some other important atomic pioneers: Chadwick, James: Discovered the neutron in 1932. Joliot-Curie, Irene and Frederic: Daughter of Marie and Pierre Curie, and her husband. Were the first to make artificial radioisotopes in 1933.