Here is a brief excerpt on some research I have been doing on the Union river sailors and they’re experiences aboard the gunboat fleet.
Tight quarters surrounded by iron plating, boilers with an insatiable appetite for coal, poor ventilation, little wind and a lot of sun earned the river ironclads the handle of “federal baked ovens.” Life in the river navy was fundamentally different from life aboard men-of-war performing blockade duty. Sailors, also referred to as bluejackets or jacks, of the regular navy enjoyed fresh air above deck and little danger; although monotonous and uneventful, save the occasional chase of smugglers, the deep water sailor enjoyed a much higher standard of living than his cousin in the brown water navy. The river sailors cruised close to land and became choice targets of confederate guerillas. The southern climate bred mosquitoes and disease, and particularly irksome to river jacks was the fact that blockaders were entitled to prize money from captured vessels while they were not. Naval officers frowned upon river service; even Flag Officer Foote confided to his wife that he would rather be commanding in the Atlantic. River navigation created another distinction between the two naval sectors.
The rivers of the Mississippi Valley were circuitous, shallow, narrow and constantly changing due to weather and floods. The weight of the gunboats caused them to frequently run aground; the constant scraping along the river’s bottom weakened the boats’ hulls causing leaks. Trees damaged the tall smokestacks or obstructed navigation. While the blockade sailor learned how to mend sails or navigate by the stars, the river tar became adept at: repairing boilers and smoke stacks, fixing leaks, and freeing their vessels from river bottoms. The narrowness of the rivers also meant that crews spent most of their time within site of land.
Not only did gunboat crews come into contact with confederate guerillas but their closeness to land brought them in direct contact with southern civilians and slaves. As the war progressed and the boats descended further south, southern plantations were freed of their cotton as well as their slaves. Many of the contraband, the union term given to former slaves, would serve aboard gunboats. Castoffs from blockade duty, transfers from the army, contraband and even some confederate prisoners-of-war would man the boats in this new navy. Although still short of manpower, enough crews existed to support the federal army advance into confederate General Albert Sidney Johnston’s precarious defensive line in early 1862.
 Michael J. Bennett, Union Jacks: Yankee Sailors in the Civil War (Chapel Hill: University of North Carolina Press, 2004), 78. Dennis J. Ringle. Life in Mr. Lincoln’s Navy (Annapolis: Naval Institute Press, 1998), 47. River ironclads consumed 2000 pounds of coal per hour when cruising at 6 knots.
 James M. Merrill, “Cairo, Illinois: Strategic Civil War Port,” Journal of Illinois State History 76 (winter 1983): 251-52; Bennett, Union Jacks, 94-95. Gunboat crews became adept at stealing cotton throughout the war. Cotton became prize money for the river sailors.
 Bennett, Union Jacks, 83-85. A gunboat sailor described the Cumberland River as, “so crooked that sometimes a steamer a half mile ahead of us would be apparently coming directly in the opposite direction and suddenly turn around a bend and lo’ she proves to be going up the river.”
 Bennett, Union Jacks, 80. Merrill, “Cairo, Illinois,” 251;255.