Hi, all!

In "The Great Catsby", by F.Scott Fitzerald, I read this:

-----Beginning of the citation-----
The Carraways are something of a clan, and we have a tradition that we're
descended from the Dukes of Buccleuch, but the actual founder of my line was my
grandfather's brother, who came here in fifty-one, sent a substitute to the
Civil War, and started the wholesale hardware business that my father carries
on to-day.
----- The end of the citation -----

What is "a substitute to the Civil War"?

Bye, all!
Alexander Koryagin

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