A big H/T to Terry for sending!! :o)
Ringing Rocks County Park is a Bucks County park in Upper Black Eddy, Pennsylvania at 40.56316°N 75.12689°W. Originally, the land was acquired by the Penn family from the Lenape (Delaware Nation) through the infamous 1737 Walking Purchase. It is not clear who made the original land warrant for the area now covered by the Ringing Rocks County Park. On the 1850 property map of Bucks County, the owner appears to be Tunis Lippincott; however, there is no warrantee listing under that name. The earliest published description of the Bridgeton boulder field is found in Davis 1876. The seven-acre boulder field was purchased in 1895 by Abel B. Haring, president of the Union National Bank in Frenchtown, NJ. Apparently Haring wished to protect the ringing rocks from development, and even refused an offer from a manufacturer of Belgian blocks for the right to quarry the stones. (Humphreys 1905, Sigafoos 1935). On August 22, 1918, the land which contains the Bridgeton boulder field was donated by Haring to the Bucks County Historical Society. The grant included 7 acres 8.08 perches of land. A right-of-way was granted by John O. McEntee for access to the park (Fackenthal 1919). Later the land was transferred to Bucks County and operated as a county park. Additional land acquisitions have increased the size of the park to 128 acres. Ott procured the musical rocks from a nearby boulder field in Upper Black Eddy, Pennsylvania. Known today as Ringing Rocks Park, the rock field occupies 7 acres of an otherwise wooded area, and is over 10 feet deep with boulders. Only about a third of the rocks ring, and for a long time why the rocks rang at all was unclear. However, in 1965 a group of scientists crushed, broke, and sliced the rocks. After performing numerous tests, they found that while all the rocks do in fact ring, they often do so at tones lower than the human ear can perceive. Interactions between these low tones create any audible sounds. However, the exact mechanism by which they ring still remains elusive, and it may have to do with the freeze-thaw cycle that helped created the boulder field in the first place. Though many are tempted to illegally pocket a ringing rock for later use, it is futile, as the rocks lose their musical ability once taken away from the other stones. Other areas in Eastern Pennsylvania are Stony Garden in Bucks County, Ringing Rocks Park near Pottstown, Montgomery County and the Devil’s Race Course in Franklin County.