Sparks Shot Tower - Philadelphia, PA - War of 1812 on Waymarking.com

History
Sparks Shot Tower was built to fill a need for lead shot created by the 1807 Embargo Act, which cut off the supply of foreign goods. Plumbers Thomas Sparks, John Cousland and John Bishop raised the 142-foot tall structure to turn out shot for sport purposes. During the war of 1812, they began to supply munitions for the U.S. military, at the request of the federal government. Bishop, a pacifist Quaker, sold his share of the business to Sparks as a result of the change in production to purposes of warfare. During this era, Merchant Paul Beck built another separate and larger brick tower near 21st and Cherry Streets in late 1808.

Tons of ammunition were produced at both of Philadelphia’s shot towers during the War of 1812. (It was said that they could provide enough ammo for all of America, plus Asia.) In 1815, to celebrate the end of the War of 1812, Beck’s obelisk was lit up like a pillar of fire, the top crowned with a hundred and sixty lamps. But by 1828, Beck closed his factory. Demand for shot had fallen to only a fraction of its 5-ton daily capacity and increased competition from other plants across the country hurt sales.

Unlike the shot tower in Baltimore, this one cannot be got to by pedestrians. It was fenced off and had a huge, high, brick wall added to the perimeter for good measure. I could see this a half mile away on my approach. It looks like a smoke stack with a lid on top, but it's really America's first shot tower built in 1808. Shot towers revolutionized the making of musket balls and other solid projectiles based on the principle that molten lead will form perfect round balls when poured from a high place.

Until this discovery, gun shot was made by pouring the lead into wooden molds. Plumber Thomas Sparks and a partner created a 142-foot-high brick tower with a 30-foot circumference at its base tapering to 15 feet at the top. It stands along the Delaware River waterfront at Carpenter Street in South Philly and is easily seen from Route I-95. The molten lead was poured through a mesh with different sized holes for different sizes of shot. The balls fell into a large container of water. Four generations of the Sparks family kept the tower in operation until 1903. The tower is now part of a city playground with a recreation center at the base. It's a prime example of Philadelphia's reputation for superb brickwork.
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The blue PHMP marker outside the perimeter wall reads:

First in the nation. Built 1808 by Thomas Sparks & John Bishop to make hunting shot, it symbolized a new U.S. industrial independence. Bishop, a Quaker, sold his share when ammunition was made here for the War of 1812. The Sparks family stayed in control until 1903