Rittenhouse Square, one of William Penn's original five, was known
as the southwest square until 1825 when it was named for the
astronomer-clockmaker, David Rittenhouse (1732-96). This amazing
man of universal talents — one of many in 18th century Philadelphia
— was a descendant of William Rittenhouse, who built the first
paper mill in America in Germantown. He was at various times a
member of the General Assembly and the State Constitutional
Convention, and president of the Council of Safety. His survey of
the Maryland-Pennsylvania boundary in 1763-64, to settle a dispute
between the Penns and Lord Baltimore, was so accurate it was
accepted and followed by Charles Mason and Jeremiah Dixon when they
surveyed the "line" for which they are still remembered. Professor
of Astronomy at the University of Pennsylvania and inventor of the
collimating telescope, he was also president of the American
Philosophical Society and the first director of the United States
Mint.
Unlike the other outlying squares, the early Southwest Square
was never used as a burial ground, although it did offer pasturage
for local livestock and a convenient dumping spot for "night
soil".
By the late 1700's the square was surrounded by brickyards
because the area’s clay terrain proved better suited for kilns than
for crops.
By the 1850's a building boom began, and in the second half of
the 19th century the Rittenhouse Square neighborhood became the
most fashionable residential section of the city, the home of
Philadelphia's "Victorian aristocracy." Some of the mansions of
that period still survive on the streets facing the square,
although most of the grand homes gave way to apartment buildings
after 1913.
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