Over the roar of a backhoe and the shriek of power tools, archaeologist Rebecca Yamin stood on the edge of a dusty pit and examined what was left of the western wall of the Van Dyke Building, which stood at Third and Chestnut Streets in the middle of the 19th century.

It was the last piece of a puzzle in four dimensions - mapping the site of the Museum of the American Revolution over more than 250 years.

"The philosophy behind this work is, if you're going to destroy a site that's historic, we map all the features so at least there is a record," said Yamin, of the Commonwealth Heritage Group in West Chester.

What they unearthed in the fieldwork, which began in July 2014 and concluded last week, was a record of the city's built environment, containing thousands of objects that belonged to people who lived here.

"We could tell the story of Philadelphia in microcosm from that one place in the oldest part the city," Yamin said.

Of course, in the context of the museum, the Revolutionary War-era artifacts are the most prized. Dozens of those finds will be exhibited once the museum opens next spring, said Scott Stephenson, vice president of collections and interpretation.

"I jokingly showed up at the site and said, 'Can I put an order in for a 'No Stamp Act' teapot?' " he said. He was referring to one of the best-known artifacts from the era: a protest in porcelain to taxation without representation. Two hours later, a worker texted him a photograph of a fragment. It was part of a punch bowl bearing an image of a sailing vessel above the text "Success to the Triphena."

In 1765, the ship carried a message from Philadelphia merchants to manufacturers and merchants in Great Britain, urging them to lobby for the Stamp Act's repeal.

"It shows how valuable historical archaeology is," said Stephenson. "It's tough when you walk around the Old City neighborhood and you see construction and realize how much is being hauled away and the sites aren't being excavated. That's information that's just hauled away to a landfill."

In this case, the museum spent about $820,000 to bring in Yamin's team. Because of a tight timeline, they worked alongside the contractors. "There was no saving anything for later," she said.

Yamin was surprised by how many features remained undisturbed: 50 foundation walls and brick-lined shafts, the oldest dating to around 1730. The objects residents and workers dropped into those wells and privies tell the story of a city in flux.

There were mysteries down there, such as a cache of tankards, glasses, and punch bowls, including the Triphena punch bowl, in a privy at an address that was once 30 Carter's Alley.

The artifacts suggested a tavern. But Benjamin Humphreys, who owned the property, was a toolmaker, and there was no tavern license. The team was stumped - until they found a reference to a Mrs. Humphreys being charged with running a "disorderly house" there.

Stephenson noted that the Humphreys' privy dates from 1776, the year of the Declaration of Independence, to 1789, the year the Constitution took effect. "It encompasses one family's Revolutionary War experience, through their trash," he said.

Yamin's team was also able to draw connections to other historical excavations, such as the National Constitution Center site. There, archaeologists found the 1790s home of James Oronoko Dexter, a free African American and a founder of the African Episcopal Church of St. Thomas. On that site, they found earthenware dishes from the tavern where Dexter worked on Chestnut Street - owned by Joseph Yates, who had signed Dexter's manumission documents.

"We're discovering an underground history," Yamin said, "and the fragments can be joined together to tell more complete stories about people who are otherwise unknown, people who aren't the Founding Fathers. That's the flesh of history."

There's also the record of the neighborhood itself as it evolved from residential to commercial and then industrial uses.

A well filled with hundreds of lead bars, for example, offered a clue to a new business on the alley.

"We found in the lab that at the tip of each bar, you could see a letter. It was print type," said Kevin Bradley, a project archaeologist. By the mid 19th century, Carter's Alley had become a nexus for printing. This type came from a newspaper: The Inquirer, which was quartered on the alley from 1840 to 1863.

There were also the granite foundations of the Jayne Building, an eight-story proto-skyscraper that was the tallest building in Philadelphia when it was erected in 1850. It was home to Dr. David Jayne, who turned his Victorian-era patent medicine business into an empire, and it later housed the Lippincott button factory. The National Park Service demolished the building in the 1950s.

Many walls will remain buried in place, but some of the artifacts will find their way into the museum. Some will be displayed in what Stephenson calls "immersive environments" - an 18th-century tavern, a home, a meetinghouse, an encampment - designed to appeal to school-age visitors.

Stephenson thinks visitors will be especially intrigued by locally made earthenware and porcelain, a precursor to today's maker movement.

The museum will retain objects relevant to the Revolutionary era, and will donate the rest to the State Museum of Pennsylvania.

Even those not relevant to the war, Yamin said, tell a story: "How cities change, and how quickly they change. . . . We're catching the dynamic of change in a quarter of a block."