Roman Music was popular among the people, but the Roman Nobility thought all music or musicians were rather vulgar. Music was played in the theater and at private parties. It accompanied many religious ceremonies, with other public events like gladiatorial shows. There are many types of Roman musical instruments. Some of the most popular ones are the water organ, sistrum, cithera, panpipes, double flute, reed pipe, and the lyre. A Greek invented the water organ in the 3rd century B.C. It used a pump to force water into a closed chamber, thus compressing the air inside. A system of hand operated valves then released bursts of this compressed air into a set of musical pipes producing notes or chords like a modern organ. The sistrum was a sacred instrument in Roman times. It is a u-shaped metal hoop pierced with three or four holes through which thick wires were threaded. When shaken, it makes the sound of rustling papyrus reeds. The cithera, is a string instrument that is played at many social gatherings, with a pipe, to entertain guests as they talk. The panpipes are in the flute family. They are made from a row of reed tubes of graded lengths tied together to produce different notes. They take their name from the rustic god Pan, who believed to have invented them. The double flute is a wind instrument that has many different depictions. Some of them are vertical, some are horizontal, and some were over two feet long that needed an arm stretched out to play them. The reed pipe is a wind instrument that produced lod notes suitable for outdoor events. Sometimes it accompanied prayers and sacrifices. The lyre is a roman instrument with Greek origin, that was often seen in the hands of Apollo, both the son god, and patron of music. In Roman times, music was a more pleasant and peaceful form of entertainment. Unfortunately, even though we know so much about Roman music and what people thought about it; we will never actually know what it sounded like.