Vehicle horn horn. Bicycles often have a classic "bulb horn", operated by squeezing a rubber bulb attached to a metal horn. Squeezing the bulb forces air through a steel reed located in the throat of the horn, making it vibrate, producing a single note. The flaring horn matches the acoustic impedance of the reed to the open air, radiating the sound waves efficiently, making the sound louder. Other types of horns used on bicycles include battery-operated horns (sometimes even car horns on 12-volt circuits are incorporated) and small air horns powered by a small can of compressed gas. Oliver Lucas of Birmingham,
John A. Horn 1996 from the University of Virginia School of Law. John A. Horn John A. Horn is an American attorney. Currently with the law firm King & Spalding, he is a former United States Attorney for the Northern District of Georgia. During his 15-year tenure with the U.S. Attorney's Office in Atlanta, Horn served as deputy chief of the Narcotics & Organized Crime Drug Enforcement Task Force, then Appellate Division chief and first assistant U.S. attorney under Sally Yates. Horn became acting U.S. attorney after then-President Barack Obama nominated Yates as Deputy Attorney General. When Horn's term expired in December 2015,