alternatehistory.com

27 May

The sloop Marion is brought to bay. Her attempt at raiding British commerce in the Mediterranean, while extremely courageous (and somewhat effective, due to the diversion of resources to North America) has finally resulted in her luck running out, and the HMS Leopard engages her in the Adriatic.
Both ships are not the newest vessels in their respective navies by any means - indeed, the Leopard is a paddle frigate, and carries the same number of guns as Marion (though a greater throw weight - Marion carries 18 32-lber guns, Leopard is armed with no fewer than nine heavy Armstrong rifles) - but the Marion has no engine, rendering her at a significant disadvantage under normal conditions.
The two ships engage repeated broadsides as they head towards the Croatian coast, following a fresh wind which minimizes the disadvantages of the American vessel, and Marion attempts to duck through the islands to gain escape - unfortunately for her, Leopard's captain guesses correctly on the route Marion is attempting to take and manages to hammer her with an accurate rifle salvo from the starboard quarter which dismasts her.
After this, the Marion strikes - unable to manoeuvre at all now, it would be trivial for Leopard to get a position on Marion's bow or stern for a rake. Nevertheless, Marion's action was well fought against a much heavier vessel and her captain is commended by that of Leopard.



28 May

Union troops fall back from Ann Arbor in the face of superior artillery.
At about the same time, the Mound City is engaged by the CSS Mississippi south of St Louis.
The unusual design of the Mississippi means that the projected top speed of the Confederate ironclad is not in fact attainable - she can only make 10 knots instead of the intended 14 - but this merely makes her no faster than the Mound City, and the Eads boat finds herself at an overall disadvantage as the Mississippi is enormous.
Half again as long and with more than twice the draft, the 3,800 ton Mississippi carries eight 9" smoothbores in each broadside and four 7" Brooke rifles as her chase guns in addition to 3.75 inches of layered armour specially made in an Atlanta foundry.
By comparison the Mound City is small and poorly protected, with a 2.5 inch casemate, and carries only 14 guns total (three 8" smoothbores, 4 42-lber rifles and six 32-lber rifles, as well as a lone 12-lber rifle). Her main advantage is her shallow draft, but this is not initially realized (the Mississippi does not look as fearsome as she is, as her unconventional 'house' construction gives her an unusual and deceptive profile, a problem exacerbated by the drizzling rain) and the Mound City gets closer than she should.

For the first quarter hour of the engagement, there is little major damage done by either side - Mound City's guns are mostly unable to penetrate the shield of the Mississippi, and Mississippi's crew are quite new at their task - but Mound City is unable to disengage easily, as (like all City class ironclads) her stern is unprotected and hence she cannot steam directly away.
Some minutes into the engagement, Mississippi scores a hit on the hull of Mound City. As this is also unprotected, it causes a major problem of incoming water - not as serious as it would be on a no-reserve-bouyancy monitor, but Mound City begins to list. This skews off the angle of her casemate, and the Mississippi's next salvo with the smoothbore guns scores two hits which penetrate the relatively thin iron.
Mississippi's fire hits the steam drum of the Mound City's engine, and steam bursts through the crew, transforming the ironclad into a catastrophe in moments as hot steam fills the entire casemate - the only crew to escape with relatively few injuries are the ones who jump straight into the water.
Mississippi is hardly unscarred - her own armour has had plates racked off in places, and several small injuries took place due to inexperience with the heavy guns - but her defeat of Mound City is an important one for control of the Mississippi River.




(This is a slight potential handwave - I'm not sure if Mississippi would in fact have been finished by this time - but she was launched and the person building her thought there were only a few weeks in it. Chalk it up to less pressure on New Orleans' defences and hence less militia drill if you have to.
As for the success of Mississippi, well, she was quite a beast (and OTL the Mound City was basically killed by a solid shot from an old 32 lber gun in pretty much this fashion, just from shore guns.) Another of the nearly-finished CS Ironclads which seem to show them going for quality over quantity - a reasonable approach, given their situation.)