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Greenpoint Playground

Right Triangle Playground

This text is part of Parks’ Historical Signs Project and can be found posted within the park.

The Greeks were famous for their fascination with proportion and symmetry, and it is from them that we get the mathematical definition of the right triangle. Although the Egyptians and Babylonians were aware of its existence and familiar with its properties, we regard Pythagoras of Samos (c.569BC to 475BC), famous for his Pythagorean Theorem, as the great definer of the “right.”

By definition, a right triangle must contain one 90-degree angle and two smaller, acute angles. Pythagoras found the following to be true for every right triangle: by treating each side as if it were a square, the total area of the two smaller squares would be equal to the area of the largest square: a²+b²=c², hence his theorem. This playground, though not strictly a right triangle, bears such a close resemblance that in 1999, Parks Commissioner Stern found it apt to name the playground in celebration of that grand triangular form, a geometry lesson in concrete and asphalt.

Right Triangle Playground lies in the neighborhood of Greenpoint, at the junction of Franklin, Commercial and DuPont Streets. When European mariners arrived here in the 17th century, they called the entire peninsula “Greenpoint” because of a grassy bluff on the bank of the East River. The Dutch bought Greenpoint, including what would become Williamsburg and Bushwick-Ridgewood, from the Keskachauge in 1638 and named it Boswijck (Bushwick) Township. A Scandinavian ship’s carpenter, Dirck Volckertsen, acquired Greenpoint from the Dutch in 1645. The land then passed to a Dutch military captain, Pieter Praa, and afterwards to an inventor and industrialist, Neziah Bliss.

For almost two centuries, the area thrived agriculturally and remained isolated from the rest of the region. At the time of the Revolutionary War, only five families lived in the Greenpoint area. Annetti Bennett, Pieter Praa’s daughter, and her husband Jacob built the first house near the playground site. This house was close to present-day Clay Street, between Manhattan Avenue and Franklin Street. The first road was built in Greenpoint in 1838, and a regular ferry service followed soon after.

When Greenpoint’s streets were further laid out in the mid-19th century, they received a letter designation in alphabetical order, running roughly southeast starting with A Street and ending with O Street. Many neighborhood residents did not like these initial names, and the streets were renamed with more colorful names, while keeping pattern. A Street became Ash Street, followed by Box, Clay, DuPont, Eagle, Freeman, Green, Huron, India, Java, Kent, Lincoln, Milton, Noble, and Oak. Lincoln Street was later changed to Greenpoint Avenue.

Industrialization and an influx of residents soon followed, flooding the newly laid streets. The area became known for shipbuilding, as well as for what were known as the five “black” arts: printing, oil refining, cast iron manufacturing, and glass and pottery making. By 1875, more than 50 oil refineries were located in Greenpoint, Williamsburg, and Bushwick. Charles Pratt’s great Astral Oil Works were located along nearby Newtown Creek. Notable products from Greenpoint include the first ironclad warship, The Monitor, built by Thomas Rowland’s Continental Ironworks at Calyer and West Streets. Examples of the wrought ironwork created during that period can still be seen in the details of Greenpoint residences and businesses today. Immigrants from Ireland, England, Russia, Italy, and Poland crowded into Greenpoint during the late 1800s to work in the factories. By the 1990s, more than a third of Greenpoint’s residents were Polish immigrants or of Polish descent, giving the neighborhood the distinction of having the largest concentration of this ethnic group in the United States.

The City of New York acquired this property in 1925. The small set of concrete steps facing Franklin Street mark the spot of a comfort station that was removed in the 1990s. Right Triangle Playground is ringed by beautiful shade trees, beneath which are benches, providing a cool respite for the hot and tired during the summer months. A playset with safety surfacing, toddler and child swings, and a spray shower give children ample outlets for activity. A flagpole and yardarm displays the flags of the United States, the City of New York, and Parks. The park is well lit at night by a large lighting tower.

Park Information

Directions to Greenpoint Playground

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