Schuylkill River at Penrose Ferry Bridge, Philadelphia, Philadelphia Co., Pennsylvania, USAi

Regional Level Types
Schuylkill River at Penrose Ferry Bridge	Bridge
Philadelphia	City
Philadelphia Co.	County
Pennsylvania	State
USA	Country

The deposit of clay underneath the city of Philadelphia, ten miles square with an average depth of fifteen feet containing a diffusion of gold. The weight of one hundred and thirty grammes of clay, duly dried and treated, yielded one eighth of a milligram of gold, a very decided quantity on a fine assay balance. Experiments were repeated upon clay taken from the cellar of a new market-house in Market Street, near Eleventh Street, at the depth of fourteen feet where it could not have been an artificial deposit, and from a brickyard in the suburbs of the city with nearly the same result. The assays gave seven-tenths of a grainsay, or three cents worth of gold to the cubic foot. Assuming the data already given, we get four thousand one hundred and eighty million cubic feet of clay under the streets and houses. Although void of value, the corporate limits of the city would afford eight times this bulk of clay, amounting to more gold than has yet been brought to market, according to the Statistics from California and Australia (1861).