Transportation.—The earliest methods of transportation were by horseback riders, stage-coaches and steamboats. The advent of railroads in 1834 marked the beginning of a vast change in mail transportation. In 1838 Congress declared railroads which were or might be completed post roads. The great extent of this development is shown by the fact that in 1927 mails were carried over 226,965 m. of railroad. In 1927 there were 6,350,589586 lb. of mail transported by all methods most of which was by railroads.
The earliest use of the aeroplane for carrying mails was under occasional authorizations to postmasters to dispatch mails by planes in connection with fairs and other exhibitions. In 1918 Congress having made an appropriation, an air mail route was established between New York and Washington by way of Phila delphia. In 1919 the service was established between New York and Cleveland and in 1920 the transcontinental route, New York. to San Francisco, was put into operation. This provided a sched ule of 32 hours and 3o minutes west-bound and 29 hours east bound. The first through day and night service was started July I, 1924. The department established and maintained the Gov ernment-owned air mail service over the transcontinental route until its practicability was demonstrated and then released the line to contractors for its operation. There are (1928) 20 con tract air mail routes with a total mileage of 10,932 m. each way. Direct contract air mail connection is made between 98 of the more important cities in the United States. During the fiscal year 1928 there were 1,861,800 lb. of mail carried by air mail; m. of service were actually flown.
Experimental transportation of the mails by 6-inch pneumatic tubes underground was inaugurated in Philadelphia in 1893. The present system consists of 26.99 m. of double lines of 8-inch tubes in New York and Brooklyn and 1.6 m. of double tubes in Boston. The larger percentage of the letters passing through the postal points connected by the system are transmitted through the tubes.
Special Services.—With a vast organization touching every locality and equipment at its disposal for postal purposes, the postal establishment has taken on various activities that can be assimilated with the general service and best performed for the public by that means. Among the principal ones are the following :
A uniform system of registration for mail matter was established in 1855 to insure the greater security of valuable letters. The system has been applied to the first, second and third classes of mail matter and extended to the foreign as well as domestic mails. Domestic third and fourth class matter may be sent collect on-delivery on the payment of a special fee; that is, the price of the article and the charges thereon will be collected from the addressee. This service was inaugurated in 1913. The money order system was established in 1864. Under this system a patron may for a specific fee purchase a domestic money order in stipu lated amounts not exceeding $100. This may be paid within a limited time at any money order post office. Under separate con ventions with foreign countries an exchange of money orders is provided for. This was inaugurated first with Switzerland in 1869 and Great Britain in 1871. The Parcel Post Act (1912) cre ated markets for merchandise throughout the entire country.
Prior to 1913 fourth-class matter constituted only about 5% of the total weight of the mails. Under the new system parcel post has grown to be 60.5% in weight of the mails.
For special fees a service of "special handling" is given fourth class matter and special delivery is given all classes of mail.
The postal savings system was inaugurated in 1911 and provides for the deposit of savings at interest with the security of the United States Government for repayment on demand. Simple in terest at the rate of 2% per annum is paid. At the end of the fiscal year 1928 postal savings deposits were received at 6,679 deposi tories and there was remaining to the credit of depositors the sum of $151,000,000.