David Rittenhouse (1732-1796), the maker of Drexel University's Astronomical Musical Clock, was Philadelphia's most noted astronomer, mathematician, scientific instrument maker and surveyor during the 18 th century. His clock dates to c. 1773 and has been regarded as the most important clock in America.
The uppermost dial is an orrery that gives the positions of the then-known planets: Venus, Earth, Mars, Jupiter, Saturn and Mercury.
The lunarium in the center dial shows the phase of the moon at the particular time that appears on the clock.
The four filigreed hands indicate the hour, minutes, seconds and month. The numerical date is shown in an aperture in the center of the dial. The clock strikes quarterly and hourly and plays ten tunes.
The four corner dials show the positions of the sun and the moon in the zodiac, the moon's orbit around the earth, the equation of time and numbers one through ten are a tune selector.
The sliding bar on the left determines the frequency of the striking and the bar on the right determines the frequency of the musical chimes.
Inscribed on the dial is “David Rittenhouse Fecit.”
The Chippendale Astronomical Clock was given as a gift to Drexel Institute in 1894 by the widow of George W. Childs, best friend of Anthony J. Drexel.
The clock is on display in the Anthony J. Drexel Picture Gallery on the third floor of the Main Building, 32nd and Chestnut Streets.