Tha nk you, it is good to be back home.
John L porter's son wrote a book about him but I don't have a copy and I believe it's long out of print. Unless of course someone here knows better !
William Wag(g)ner - I've seen it spelt both ways, is a bit of an enigma. The name is of Netherlands origin. I first came across him at Yazoo City where he was sent (By Mallory?) to assist operations there. He next was sent to Charleston to assist Duncan Ingraham.
There he was responsible for the alterations to CSS Palmetto State and CSS Charleston. How much of CSS Columbia as completed is his work seems to be a moot point. Promoted to full Constructor rank, From Charleston he was moved at John L Porter's request to Mobile to replace Joseph Pearce - in fact he went to Montgomery where the yard manager was struggling with what became CSS Montgomery.
The latter move was caused by Franklin Buchanan, who complained to Porter about Joseph Pearce (in fact the poor man was ill).
As an aside , Buchanan was something of a bully used to getting his own way - after an acrimonious spat with Porter, the latter telegraphed Mallory to request his removal from command at Mobile. If Mallory reived the message he obviously either refused or did nothing - with the result we all know.
Porter told him the nearest Constructor available was Sydney Porter (John L's brother). Buchanan was having none of it (" He's a drunkard"), So Wag(g)ner was asked to go to Mobile but found there was no constructor at Montgomery where a second Nashville type hull was being built at Buchanan's instigation.
Sadly although the ships hull and machinery was sound, the armour supplied, for whatever reason was wrong, so that Wag(g)ner had to make what use he could, plus putting some of his own ideas into the ship. The result was a failure, being overweight even without ordnance. At Mobile the armour was stripped and she became a transport.
It seems Wag(g)ner had ideas for a twin screw ironclad to be built at Montgomery - presumably with a Nashville type hull as the yard staff would be familiar with it, machinery by Warner at Columbus, armed with heavy breechloaders, He apparently told or discussed this with John L Porter who suggested he talk to Catesby Jones at Selma.