The New York Times offers PDF's of some interesting old articles on sock knitting for soldiers.
Here are two links from the Times in 1914: the link will open in to a downloadable PDF of the original articles!
Mrs. DeLancey Nicoll's instructions on "How to Knit Socks for Soldiers" Apparently, Mrs. Nicoll interviewed a woman from the Red Cross who stated: "The trouble with American women is that so few of them know how to knit socks. Practically only the foreign-born women know how."
And finally, from 1917, a general article including socks:
The Times has some other fascinating articles both old and new on knitting. Go to NYTimes.com and search, although you'll want to specify a little in your search e.g., "knitting socks."
In the meantime, my authentic Civil War socks are completed