Carter would have picked up the letter and handed it off to the post office. Fee was 2c.
This cover is not listed in the USPCS 1847 cover census, although 3 other Philly covers with Carters adhesives and/or handstamps are listed.https://www.uspcs.org/resource-cent...over-census/
Please see this page and think about submitting an image for the census (and you might want to have it sent to the PF for a certificate, as it's probably worth a few bucks if genuine. Also, the PF should be able to tell you if a Carters stamp was removed, though there does not appear to be any sign of one having been on the envelope from the scan.