Randy Leishman, age 13, of Bountiful, Utah, for his question:

Who invented the stethoscope?

If you visited a doctor in the year 1800, chances are he would bend over and place his ear to your chest. He was trained to recognize the sounds of your pulsing heart and tell whether its heat was normal. His trained ear could recognize an abnormal heart beat and often diagnose its ailment. SeverAl physicians tried using a length of tube to do a better listening fob but no one kept a record of these homemade inventions. Then, in 1816, a French physician made the first instrument that can be called the ancestor of the modern stethoscope. His name was Rene Laennec and most historians credit him with the stethoscope invention.

A modern stethoscope is a Y shaped arrangement of rubber tubes. The fork has two ends of metal made to fit into the doctor's ears. The single line ends in a special device that picks up internal sounds when placed on the patient's body. The sensitive instrument carries high sounds or low sounds from the heart beat, the veins and the arteries, the lungs and the intestines. It shuts out other sounds, which is why a doctor with a stethoscope in his ears is deaf to conversation.