Airplanes came into wide use during World War I, and so did aerial photography for reconnaissance. After the war, Sherman Fairchild (1896-1971) founded the Fairchild Aerial Camera Corporation. One of its earliest projects was this photomosaic of Manhattan, a combination of 100 photographs taken at 1,000 feet.

I’m currently obsessed with Central Park, so I started squinting at its details. I’ve numbered some major changes on the low-res image below. To see them, you’ll have to look on the Library of Congress site, because my computer refuses to cope with the LC’s high-res file. (What the devil is a JP2 file, anyway?)

- The Pond at the southeast corner is still full-size; the Wollman Rink wasn’t placed at its northern end until several decades later.
- Just north of the Pond, the zoo is the pre-Moses version.
- The old reservoir is still there and still filled with water. It’s now the Great Lawn.
- The Metropolitan Museum, just east of the old reservoir, is notably smaller: six new wings were added beginning in the 1970s.
- The American Museum of Natural History, west of the old reservoir, is even more notably smaller.
- On the east side toward the north end, the old conservatory is still there. The Conservatory Garden dates to the 1930s.
- There are no playgrounds around the edges of the park. Even the Heckscher Playground at the southwest corner wasn’t built until 1926, although there was a baseball-playing area there earlier.