Apparently, the letters P.O.D first started appearing in 1873. Check out this link:
http://www.usps.com/postalhistory/_pdf/carrbuttons05.pdf
I found this button near a southern CA adobe that was built in the 1850s. This design was used between 1873 and 1893, when it was replaced by a design featuring a walking mail carrier, midstride, holding a letter in his outstretched hand. - Jim
http://www.usps.com/postalhistory/_pdf/carrbuttons05.pdf
I found this button near a southern CA adobe that was built in the 1850s. This design was used between 1873 and 1893, when it was replaced by a design featuring a walking mail carrier, midstride, holding a letter in his outstretched hand. - Jim