Lot 161822 (Apr. 4) Philadelphia Pa. to Schiedam, Holland via Hamburg, folded letter carried by private ship to Hamburg, endorsed "per Ship Recovery" at bottom left, entered mails with "Hamburg" straightline across back flaps and "Hamburg Post Office for America" oval handstamp (der Linden 2251) showing castle, red crayon "4" rating adjacent, Very Fine and rare Hamburg marking.
Estimate $500 - 750.
The Hamburg Castle oval is a state postal marking, quite unusual with writing in English. We only have seen recorded four examples of this marking on mail from or to the United States.