Someone wanting a brief survey of the role of the gunboats during the Civil War on western waters will find this book moderately useful. My view is that it spends too much time on the Confederate river forces, given their almost utter lack of success and strategic insignificance after the battle of Memphis. Also I would question the selection of the battle of New Orleans as illustrative of the usage of gunboats on the rivers; the Confederate gunboats in that battle were handled terribly, and they were up against ocean-going warships, hardly typical of western gunboat fighting. Much better instead would have been to treat one of the operations on the White or the Yazoo. But reasonable people might disagree.
I was very disappointed, however, to encounter some grave errors. It says on page 46 that "The 'walking beam engine' was the most common type of engine used on the paddleboats that plied the western rivers in peace and in war." That is entirely false. By at least 1830 and probably even earlier, the walking beam transmission (typically associated with low-pressure engines, and essentially always with vertical cylinders) had been entirely superceded on the western waters by the Evans-type, horizontal-cylinder, high pressure steam engine, with direct drive from the piston rod to an oscillating "pitman," a wooden beam that turned the crank of the paddle wheel. The principal motion of the pitman was fore-and-aft, though it moved up and down just enough to accomodate the rotation of the crank. Since the high-pressure boilers associated with the Evans-type engine were responsible for a number of grave tragedies during the war (notably on the USS Mound City and the USS Essex) as well as a number of fabled steamboat explosions in time of peace; and since hard work of getting over bars during low water in peace or war almost dictated the use of high-pressure engines, this really is an egregious error.
But worse. The centerfold colored, cutaway diagram of the USS Queen of the West is not only utterly conjectural, but it is almost certainly false in key respects. (Continue reading only if you want to hear the details of its misleadingness.) The engine shown appears to be of a compound type, with two in-line cylinders of different sizes -- nothing like the single-cylinder, high-pressure engine with which the Queen was almost certainly equipped. Compound engines were quite rare on the rivers until after the war. The piston rod emerges from the cylinder at an angle, a technical impossibility. It appears to be connected directly to the crank, another impossibility. There are no cylinder braces, so the engine should fall down onto the deck. There is no pitman, no crosshead to connect it to the piston rod. The paddle wheel in the diagram appears to be of metal; but western river wheels were all of wood (though braced by an "iron circle") -- a metal wheel could not be repaired on-the-spot in case an almost-inevitable collision with a log damaged it. The diagram includes a steam condenser -- no such thing on a customary high-pressure rig. The heads, where shown, would have emptied into the hold, a nasty buisiness; heads were usually on the guards right abaft of the wheelhouse, so that the deposits would fall into the water. Captain's day cabin and large stateroom, stuff and nonsense (what, is this an English boat?). Boatswain's store, utter conjecture. Boilers show below decks (probably on the assumption that the lowered boilers on the turtles and the timberclads were normal practice); but the boilers of this army ram, like all western steamboats, were on the main deck. The Queen was intended as a ram, with reinforced fore-and-aft bulkheads; lowering the boilers would have cut through these bulkheads, ruining the boat for its intended purpose. Boilers not long enough. No firebox, but instead, absurdly, fire door appears to enter forward end of boiler. Chimneys on the wrong side of the boiler (with return-flue boilers that were in universal use, the chimneys stood over the fire). There is more, but I can't go on.
All this shook my faith in these New Vanguard military books. In light of the serious deficiencies in the book's presentation of steamboat technology (the authors should have tried reading Louis C. Hunter's book), it doesn't deserve more than two stars. If you buy this, ignore the centerfold diagram, which is a travesty.