Can you identify the origin of this 1857 cover ?

[Peter Allan]

I have just received a cover, image below, stamped with a 4d blue no watermark chalon. Tle first allocation numeral definately has a three in it, and by the position of the three, it seems to me that this is the second digit of the number, not the first. Although difficult to see from the scan, there appears to be a "1" righ on the left margin of the stamp making it BN 13 of Bothwell, but I am not certain.
There is a signature written sideways on the left side of the cover plus the date as per the Pre-Paid stamp - 15 June 1857. Could the signature be Postmaster's signature? I cannot find any reference for the name of the Bothwell Postmaster at this time. I have added a seperate scan of the signature and date. Any suggestions welcomed.
Peter Allan

cover-1857-15-June.jpg (68.64 KiB) Viewed 92 times

1957-cover-signature.jpg (14.38 KiB) Viewed 92 times

[Jerry Weirich]

The "signature" is actually the letter carrier's endorsement which was required (but didn't always get done) on every posted letter during this period. The endorsement consisted of the post office name and date of pick up. This endorsement reads "Bothwell" with the date of 15/6/57. The barred numeral is indeed 13. Nice early cover.

[Peter Allan]

Thanks Gerry. I should have realised that the 'signature' is in fact Bothwell. Having now checked the Act and Regulations for 1853, I find the following requirement:
"DISPATCH AND RECEIPT OF MAILS. 10. Name of Post Office and Date to be written on every letter" - Regulations for the guidance of the Post Office Department 1853