Case in point, this story on the 12-pdr Napoleon Civil War cannon at Galena, Illinois' Grant Park.
I got the information from the article, then did a search on the net for Galena's cannons and found more information.
Then, I looked up Miles Greenwood's Eagle Ironworks and found information on it. He could be called one of the arsenal's of the Union with all the war-related items they built. Then, I read that he built an ironclad in Cincinnati, which sent me off there. He built one and another foundry in the city built two. Then, there was a search for information on those. I came across other Union warships built there. I didn't know that warships were built in Cincinnati, especially monitors.
I then came across four Greenwood Napoleons that are at the Ohio state house.
I'll be writing about all this stuff.
No Wonder It Takes So Long. But, It is Sure Stuff I Don't Know About. --Old B-R