A muffler is a device for reducing the amount of noise emitted by the exhaust

Exhaust gas

Exhaust gas or flue gas is emitted as a result of the combustion of fuels such as natural gas, gasoline/petrol, diesel fuel, fuel oil or coal. According to the type of engine, it is discharged into the atmosphere through an exhaust pipe, flue gas stack or propelling nozzle.It often disperses...

 of an internal combustion engine

Internal combustion engine

The internal combustion engine is an engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber. In an internal combustion engine, the expansion of the high-temperature and high -pressure gases produced by combustion apply direct force to some component of the engine...

. A US Patent

United States patent law

United States patent law was established "to promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries;" as provided by the United States Constitution. Congress implemented these...

 for an Exhaust muffler for engines was granted to Milton and Marshall Reeves in 1897.
The patent for an Exhaust muffler for engines was awarded to Milton O. Reeves and Marshall T. Reeves of Columbus, Indiana

Columbus, Indiana

Columbus is a city in and the county seat of Bartholomew County, Indiana, United States. The population was 44,061 at the 2010 census, and the current mayor is Fred Armstrong. Located approximately 40 miles south of Indianapolis, on the east fork of the White River, it is the state's 20th largest...

 of the Reeves Pulley Company on 11 May 1897. US Patent Office application No 582485 states that they have invented certain new and useful Improvements in Exhaust-Mufflers for engines ....
Mufflers are typically installed along the exhaust pipe as part of the exhaust system

Exhaust system

An exhaust system is usually tubing used to guide reaction exhaust gases away from a controlled combustion inside an engine or stove. The entire system conveys burnt gases from the engine and includes one or more exhaust pipes...

 of an internal combustion engine.