Entire letter canc. "CONSTANTINOPLE (TURQUIE)*15.MARS.50", via "ΠΥΡΑΙΕΥΣ*12.ΜΑΡΤ.1850", arr. "ΑΘΗΝΑΙ*12.ΜΑΡΤ.1850". Cachet "ΥΓΕΙΟΝΟΜΕΙΟΝ ΠΕΙΡΑΙΩΣ" on reverse. Disinfection slits. Handwritten "80" (lepta) charged as due on arrival.