Description | An illustration showing a man using a hearing-tube and a rod of wood to listen to sound travelling through two glasses placed on a wooden table. Both glasses are filled with water'. Labels indicate that sound can be heard through the hearing-tube from the glass filled with water, but no sound can be heard through the wooden rod. A caption reads 'Air tube in right ear, solid rod of wood in left ear: both in water. Left ear plugged with chewed paper.'
Subject: Physics |