Tow/Tow Cloth/Tow Rag/Tow Linen.

Colonial Loom.

Colonial Flax Wheel.

Combing or Hackling the flax linen line. To the left you can see the tow that has been combed out.

Two bundles of flax linen line. On the top pic you can just see the fuzzy strands of tow.

Tow/Tow cloth/Tow rag/Tow linen.You will often find mention of tow being used to clean gun barrels and for fire lighting. Tow does make a reasonable kindling and when I have finished using some for cleaning my gun several times, I put it in my fire-bag for fire lighting use.
Tow is the short fibres left over after combing or "Hackling" the longer flax fibres called "Line". It can be used as above, or it can be used to make tow cloth. Tow cloth was a cheaper material which was used for making work clothes, work frocks were often made from tow. A tow rag one would assume is the material from worn out old tow cloth clothing and is no longer any use for anything but to be used as a cleaning rag or perhaps for making tinder for flint and steel fire lighting. Hence I guess the term “tow rag” being used for a person who is not up to much! (1).1) http://www.csmid.com/fieldclean.html

http://www.classactfabrics.com/linen/linen_fabric.htm
http://www.netw.com/~rafter4/1871rugs.htm

http://digitalcommons.wku.edu/cgi/viewcontent.cgi?article=1005&context=dlsc_fac_pub
http://www.1771.org/ev_spin_dye.htm
www.gutenberg.org/files/21534/21534-h/21534-h.htm
http://global-language.com/CENTURY/

The top photos are curtesy of Gutenberg, and the lower photos of the linen flax are mine.