[ih] origin of term "snail mail"

[Ann Mulloy Ashmore]

Hello,

I am researching the origin of the term "snail mail."

If anyone has documentation (use in a paper, article, presentation, etc.) 
about when "snail mail" may have been first used and by whom,  I would 
greatly appreciate the benefit of your knowledge.

Thank you in advance for your time and assistance.

Ann Ashmore, Hattiesburg, Mississippi
ann.ashmore at usm.edu