Burgh (2006), suggests that the roots of Western classical music ultimately lie in ancient Egyptian art music via cheironomy and the ancient Egyptian orchestra, which dates to 2695 BC. This was followed by early Christian liturgical music, which itself dates back to the Ancient Greeks[citation needed]. The development of individual tones and scales was made by ancient Greeks such as Aristoxenus and Pythagoras. Pythagoras created a tuning system and helped to codify musical notation. Ancient Greek instruments such as the aulos (a reed instrument) and the lyre (a stringed instrument similar to a small harp) eventually led to the modern-day instruments of a classical orchestra. The antecedent to the early period was the era of ancient music before the fall of the Roman Empire (476 AD). Very little music survives from this time, most of it from ancient Greece.