When the historian and author Gil Tauber retired from his job as a city planner in 2002, he had a stack of books that he never had time to read — including an 1846 volume on the city’s religious denominations. In that book, he kept running into New York street names no longer found on present day maps. There were so many that he started to make a list. Then it occurred to him that others who were researching New York history or genealogy must have encountered this same problem. He has published the fruits of his work in an online searchable research tool called www.oldstreets.com.

“Old roads, lanes, alleys, courts, terraces, parks, squares, wharves, piers, slips, markets, and other named urban features that have been demapped, obliterated or renamed” are featured on his Web site. They number around 1,600.

Just how do street names get changed or lost over time? First, politics. After the American Revolution, New York got rid of certain vestiges of Britain: King Street was changed to Pine Street, and Crown Street became Liberty Street.

Secondly, until the early 1800s, property owners or common usage often determined street names. A single street could have multiple names: “For example,” Mr. Tauber notes, “parts of West 4th Street were formerly known as Asylum, Chester, and William Street.” In other cases, depending on the record, a street can have various names, such as Dies, Dye, Dyes, and Dyers before it settled on the present Dey Street.

Thirdly, the Commissioner’s Plan that was adopted in 1811, and which introduced the well-known grid of numbered streets and avenues, destroyed numerous streets on the Stuyvesant and Kip Estates. “A single block of Stuyvesant Street is all that remains of the street grid on the former Stuyvesant estate.”

Yet a fourth reason for street name changes is realignment after major fires. For example, after a blaze in 1835, the city lost the former Merchant Street.

Large-scale urban renewal is yet another way streets can disappear. During the two decades after 1940, a new police building and new ramps from FDR Drive to the Brooklyn Bridge took out Hague, Vandewater, Rose, Jacob, Ferry, New Chambers, and North Williams streets. Alfred E. Smith Houses obliterated Oak and Chestnut streets. Extending Sixth Avenue southward for the construction of the subway caused Hancock and Congress streets to disappear in the 1920s.

In search of these changes, Mr. Tauber examined files at the Municipal Reference Library on Chambers Street and at the Topographical Bureau of the Manhattan borough president’s office. “Neither is complete,” he said. He also poured over scores of maps, reference books, and city directories at the New-York Historical Society and the map division at the New York Public Library.

Mr. Tauber said one of the most difficult periods to research was between the 1790s and 1810, when there was enormous expansion, just prior to the 1811 plan that set out the grid.

This tracer of lost streets still has a few “loose ends.” The only vestiges of certain street names are those mentioned in the minutes of meetings such as those of the Common Council, a predecessor to today’s City Council.

Books and maps are second nature to Mr. Tauber, who has been surrounded by print from an early age. His father owned a newsstand in the Bronx. He read a lot of comic books, science fiction, and popular science and later attended Bronx High School of Science before matriculating to City College.

He was an urban explorer from his youth “on foot, by bike, and trolley car.” After serving overseas in Italy in the U.S. Army, he worked in publishing and led walking tours for the Museum of the City of New York.

He later returned to school to earn a graduate degree in urban planning. He contributed articles to the “Encyclopedia of New York City” and co-authored “The New York City Handbook” (Doubleday).

He gives walking tours of New York, and recently led two tours of Harlem in German. In June, he gave a walking tour sponsored by the Columbus Amsterdam Business Improvement District. It covered from West 96th Street to West 110th Street.

He also has a flair for the printed word himself. Around 1958, he landed the job of publicity director for Dover Publications after beating out other applicants; all were asked to write a press release announcing the expulsion of Adam and Eve from the Garden of Eden. He won.