Can anyone direct me to a web resource that offers an explanation of the duties and functions of the various civil war ranks. Especially enlisted ranks -- what were the function of 2nd, 3rd, 4th and 5th Sergeants and Corporals or Lieutenants. I understand that Captains and Field Grade officers served similar functions to those today but I'm at a loss to understand the grade structure mentioned.

And I can't seem to find a web site that addresses the issue. Thanks for your help.