"Hardtack and Coffee" - the author escapes me at present, but it is a great look at the every day lives of soldiers on both sides.
"Mr. Lincoln's Navy" - same problem (I'm not at home). An excellent account of an under-reported group of fighting men.
I'll post the authors of both of these fine books later.
Here are the details on the editions you cited;
Hardtack and Coffee,
Billings, John D, George M. Smith & Co, 1887. This is a fine book, and it's been reprinted many times, latest being 1996.
Mr. Lincoln's Navy,
WEST, Richard S., Longmans, Green and Company, 1957. I'm not familiar with this book, I'll have to check it out.