There is a cancel showing a postage payment (PAID 3) was made but no stamp. I believe the general use of postage stamps began in the USA 7 years previous in1847 but stamps may not have been widely available in small town America? Was this a commonly acceptable practice at this time?
The document on laid paper was tightly folded and I assume the letter formed the envelope as there is some remnant indication of a seal. The address is very unclear and confusing with words rewritten over other words- a postmaster's nightmare! The writer was a teenaged school girl and some of the letter was written awkwardly as well. The date handwritten in the letter was February 12th, 1854 but the postmark seems to indicate it was posted on FEB 20?? The year is not given in the postmark- was this a post office error or common practice? The town of Somerset no longer exists.
This was an interesting 3 page letter between sisters about daily family life issues. Through the local nespaper editor and historical society in Newark, Ohio (close to Granville) I was able to contact the living ancestors of these girls. Together we developed an accurate transcript and pieced together what happened leading up to and after the Civil War with this family. Two thousand acres of farm and woodland was first secured and developed by this Welsh family a few years before this letter. There are even published early photographs and accounts of the original family home and members of the family from that period.
My plan is to take a road trip to Newark with my wife in the spring to meet the family, see the beautiful Welsh Hills and donate the letter to the historical society.
Any additional postal history you can offer about the letter would be appreciated.

