Galileo's inclined plane is a wooden beam of approximately 6,7m length the top of which has a hemicircular vellum-bound notch. The vellum is used in order to reduce friction for a ball running along the notch.
Strings are clamped above the notch to reproduce the positions of equitemporal running distances of the ball. The ball touches the strings while passing underneath them producing a sound. If the distances are chosen in a proper manner, one can hear a sequence of sounds with a constant frequency. The respective distances between the strings can be correlated with the square values of the running times.
Drake, S. (1970): Renaissance Music and Experimental Science, in: Journal of the History of Ideas, 31, 483-500.
Settle, T.B. (1961): An Experiment in the History of Science, in: Science, 133(1), 19-23.
Rieß, Falk; Heering, Peter; Nawrath, Dennis (2005): Reconstructing Galileo's Inclined Plane Experiments for Teaching Purposes, in: Online-Proceedings of the 8th International History and Philosophy of Science and Science Teaching (IHPST) Conference in Leeds, UK. (Volltext)
Naylor, Ron H. (1989): Galileo's experimental discourse, in: Gooding, David; Pinch, Trevor; Schaffer, Simon (Eds.): The uses of experiment - Studies in the natural sciences, New York, Melbourne: Cambridge University Press.