This document provides information about four brass instruments of the orchestra: trumpet, French horn, trombone, and tuba. It describes the basic construction and playing technique of each instrument, including that trumpets are made of brass tubing bent into an oblong shape and played by blowing air through closed lips, French horns have finger-operated rotary valves and coiled tubing, trombones are characterized by a telescopic slide that varies the length of the tube to change pitches, and tubas are the largest and lowest brass instruments played by buzzing the lips into a cupped mouthpiece.