question:  What is the Geiger counter and how exactly is it used in the present chapters?
context: Then, remembering the dream, he added, “Oh, Dad, is it all right if I use the Geiger counter today?” “You may use the Geiger counter any time you want, Eddie,” Mr. Taylor said, “as long as you take good care of it. Suddenly the Geiger counter began clicking like everything.” But, from what I hear, there are plenty of rock formations. Still, one clue is as good as another when it comes to hunting uranium ore, I guess. It could start cavities. Get at it right away, and you’ll still have time to hunt your uranium. In fact, anything having to do with atomic science excited him. You couldn’t have a father who was head of the atomic-science department at Oceanview College without picking up a little knowledge along the way. When carefully controlled, the radiation stored up in such isotopes was used in many beneficial ways. One reason for asking that particular question was to keep from prying deeper into the subject of the radioisotope. His father usually volunteered any information he wanted known, so Eddie stuck to questions which could and would be answered. At the speed atomic science is moving today, we simply can’t afford to waste time. It took Eddie over an hour to sort out the newspapers and magazines in the garage, tie them in neat bundles, and place them out on the front curb for the Goodwill pickup. “Anything else, Mom?” he asked, returning to the house and getting the Geiger counter out of the closet. Besides, there were plenty of other places around the outskirts of Oceanview where likely looking rock formations invited search with a Geiger counter. 20 Eddie went inside and followed Teena to the kitchen. They had been ever since Eddie’s family had moved to Oceanview and his father had become head of the college’s atomic-science department. “Don’t go too far out from town,” Mrs. Ross cautioned, as Eddie picked up the Geiger counter.
output:  A Geiger counter is used to measure radioactivity. Eddie uses it to prospect the hills behind the college.
options:  A Geiger counter is used to measure radioactivity. Mr. Taylor uses it at Cedar Point.  A Geiger counter is used to measure radioactivity. Mr. Taylor uses it to measure the radiation present in the hills behind his college.  A Geiger counter is used to measure radioactivity. Eddie uses it to prospect the hills behind the college.  A Geiger counter is used to measure radioactivity. Eddie uses it to prospect Cedar Point.