6 6 1 ▁and ▁showed ▁only ▁the ▁day ▁and ▁month ▁of ▁ma iling ▁in ▁order ▁to ▁prevent ▁the ▁delay ▁of ▁the ▁mail ▁by ▁carri ers . ▁ ▁In ▁England ▁during ▁the ▁latter ▁part ▁of ▁the ▁ 1 7 th ▁century ▁several ▁post marks ▁were ▁de vised ▁for ▁use ▁with ▁the ▁London ▁Pen ny ▁Post , ▁a ▁postal ▁system ▁that ▁delivered ▁ma iled ▁items ▁within ▁the ▁city ▁of ▁London . ▁The ▁post marks ▁bore ▁the ▁initial ▁of ▁the ▁particular ▁post ▁office ▁or ▁handling ▁house ▁it ▁was ▁sent ▁from ▁along ▁with ▁a ▁separate ▁time ▁stamp . ▁Post age ▁was ▁pre pa id ▁and ▁the ▁post mark ▁was ▁applied ▁to ▁the ▁ma iled ▁item ▁by ▁means ▁of ▁an ▁in ked ▁hand - st amp . ▁Some ▁histor ians ▁also ▁consider ▁these ▁post marks ▁to ▁be ▁the ▁world ' s ▁first ▁post age ▁' st amps '. ▁ ▁In ▁the ▁ 1 9 th ▁century ▁and ▁early ▁ 1 9 0 0 s ▁it ▁was ▁common ▁for ▁letters ▁to ▁receive ▁multiple ▁post marks ▁indicating ▁the ▁time , ▁date , ▁and ▁location ▁of ▁each ▁post ▁office ▁deliver ing ▁or ▁transport ing ▁the ▁letter , ▁and ▁this ▁is ▁still ▁occasionally ▁true , ▁though ▁to ▁a ▁less er ▁extent ▁( see ▁" back st amp "). ▁ ▁While ▁almost ▁every ▁contemporary ▁post mark ▁includes ▁a ▁location ▁as ▁well ▁as ▁a ▁date , ▁in ▁ 2 0 0 4 ▁New ▁Zealand ▁Post ▁announced ▁plans ▁to ▁eliminate ▁the ▁location ▁on ▁their ▁post marks ▁and ▁include ▁only ▁the ▁date ; ▁however , ▁information