 In World War I port facilities in Boston, Baltimore, Philadelphia and even in Canada served as sub-ports to the NYPOE.An important special cargo function involved mail in which the POE was required to ensure all mail sacks were properly labeled, met the earliest sailing date and were distributed in such a way that loss of one ship would not destroy all mail destined for a unit.For troop movements the most critical timing factor was availability of the transports and sailing dates so that the most effective means of minimizing delays at the port was for the POE to control the movement of troops from their home stations to the port as well as having responsibility for ensuring troops were properly equipped and prepared for overseas deployment.