Cyrus Alger was born in West Bridgewater Massachusetts in 1781, and learned metal casting from his father. He set up a foundry in Easton, and in 1809 moved to South Boston, recently stolen (legally, of course) from Dorchester and annexed to Boston . One source has him supplying cannon balls to the government during the War of 1812.
Cyrus Alger mortar, cast in 1863, currently located on the grounds of the North Carolina State Capitol (Wikimedia Commons).
Alger's Iron Foundry, South Boston, 1852.
In 1816, Alger bought from the South Boston Land Association most of the land west of the Dorchester Turnpike (now Dorchester avenue), and soon began filling in the mudflats of the South Bay. Here, he built his foundry, and made a name for himself as one of the leading metallurgists of his time. Alger developed a process for purifying cast iron, producing a much stronger material, and produced the first rifled gun in the nation. He personally supervised the pouring of the Columbiad, the largest gun to be produced up until that time.
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The red 'X' marks the 1855 location of the Alger foundry in South Boston, and shows both water and railroad access (BPL map collection). Much of the land at the site marked above was created by Alger.
Closeup map view of Cyrus Algers' Boston Iron Works, Iron (later Foundry) street, South Boston, 1852. The South Boston (Dover street) bridge crosses the South Bay on the left, and the Turnpike to the right.The site had both water and rail access - note Alger's Wharf and the tracks of the Old Colony railroad.
Alger's gun yard, end of Sixth street, at the outer edge of South Boston (red), United States gun yard (blue) 1852. Cannon were tested by the batch. Samples would be taken from each batch, and fired into earthen walls repeatedly to test for defects. If there were no failures, the batch would be shipped.They also fired guns from Nut island, Quincy towards a target on Peddock's island.
Cyrus Alger was also active in the community. He served on Boston's Common Council and as an Aldermn. He paid to have sidewalks laid and trees planted along Dorchester avenue. He is said to have kept his workers on half time when they weren't needed, and introduced the 10 hour day to South Boston industry. When he died, stores closed along the route of his funeral, and factories all over South Boston shut down. Today, Alger cannons sit in front of Town Halls and on village greens all over the country, and are bought and sold by collectors as pieces of American history.
Sources: Gaining Ground: A History of Landmaking in Boston, Nancy S. Seasholes.
A genealogical history of that branch of the Alger family which springs from Thomas Alger of Taunton and Bridgewater, in Massachusetts. 1665-1875