Instruments of percussion, were few, and not indigenous to the Romans; such as were used came from the East, and were chiefly used in the worship of Eastern deities, at Rome. When the worship of Bacchus was prohibited, they passed away, with that licentious rite. The most complicated instrument of the ancient world, appeared in Rome during the first century of our era. It was an _Organ_, not as in the scriptural days a mere syrinx, or Pans-pipes, but an undoubted organ somewhat similar in its effect to our modern instrument. The instrument is said to have been invented by Ctesebius of Alexandria, in Egypt, who lived about 250 B. C. They did not appear extensively in Rome however, until nearly 300 years later. This organ has given rise to much fruitless discussion. In the field of musical history especially, “a little knowledge” has proved “a dangerous thing,” for where slight descriptions exist of instruments or music, latitude is left for every writer to form his own theory, to fight for it, and denunciate those who differ from it. We have seen what a battle was fought over the three little manuscripts of Greek music, what a host of differing opinions were held about the Scriptural word “Selah,” and now about this hydraulic organ, each writer mounts his hobby horse, and careers over the field of conjecture. Vitruvius, has given a full description of the instrument from personal inspection, but as his technical terms have lost all significance to modern readers, and have been translated in various ways, and as his work contained no diagrams, or illustrations of the various parts, it is useless. Some writers[64] imagine the organ to have had seven or eight stops, that is, so many different _kinds_ of tones, which would place them nearly on a par with our own. Others[65] think that they possessed seven or eight _keys_, that is so many _tones_ only. It has been a point of dispute as to what function the water performed in working it. Vitruvius is rather hazy on this point, saying only that it is “suspended” in the instrument. The water, when the organ was played was in a state of agitation, as if boiling. There are medals still in existence, which were awarded to victors in organ contests, on which this instrument is represented, with two boys blowing or pumping, but the representation is too small to clear up any doubtful points. So much is certain, the organs were very powerful in tone, being therefore the instruments best adapted to the large amphitheatres of Rome, and were extremely popular, for it was complained that young men forsook their other studies to learn to play them. The only possibility yet remaining that their construction may be known to us, is in the chance of discovering one in Pompeii.[66]