Finally–all is revealed. Sorry for the delay–the dog ate my homework.
Answer: Street and beach are both reminders of the Cambridge powder magazine, on a small island surrounded by marshland. Why a magazine? The powder magazine was for storage of arms and ammunition belonging to Cambridge residents; thus a storehouse, or a collection. Time and The New Yorker are also storehouses, or collections, of writings and photographs.
Cambridge’s stone powder magazine has recently undergone extensive renovations. For more information and photos, visit https://magazinebeach.org.
Question: The northeast side of Cambridgeport was once much closer to the marshlands along the Charles River; one street separated the marshes and the dry land. What is the name of that street? 
Answer: The street at the edge of the marsh is Brookline Street. In the map’s lower left corner, Captain’s Island and the powder magazine are labelled no. 4.
Question: Cambridgeport has one of the only (maybe the only) streets named in honor of an artist. Name the artist and the street.
Answer: The artist was Washington Allston. Allston was a well-known Romantic-era artist, known for dramatic, large-scale Biblical and historical scenes, of tormented kings and wild-looking prophets. The Harvard Art Museums hold a small collection of his work. Allston married Margaret Remington Dana, of the prominent Cambridge family; for a time the couple lived at the northeast corner of Magazine and Auburn streets (where Allston built a studio) and entertained guests such as Edmund Dana (who donated the land for Dana Park) and Richard Henry Dana Jr. (lawyer and author of Two Years Before the Mast). Allston was one of the first people Dana visited when he returned from his long voyage.
Bonus: On that same street, an Episcopal mission opened in 1886 and welcomed worshipers until 1920. In 1921, the church became the cathedral of a recently established denomination, whose founder believed that true equality and spiritual freedom could only be achieved by an all-Black religious denomination—a church attended by people of color and administered by Black clergy. Who was the church’s founder and Bishop? What is the name of the church?
Answer: St. Augustine’s African Orthodox Church, 137 Allston Street, was planted by the founder of the denomination, Bishop George McGuire, who designated St. Augustine’s as his bishop’s seat. He is honored with an African American Heritage Trail marker.
The church is undergoing extensive exterior restoration, roof, siding, and new handicapped access, funded in part by preservation grants from the Cambridge Historical Commission. The Cambridge Day has an article about the work with great photos. https://www.cambridgeday.com/2019/11/18/restoration-work-begins-at-st-augustines-winning-another-50000-matching-grant/
