"The first traces of the Arabian postal arrangements date from about fifty years after the death of Mahomed. Calif Mdowija, who died in 679, is regarded as the founder of the Arabian posts. Kodama, a native of Bagdad, who died in 959, gives an account of the service in his work called _The Book of Taxes_. There were 930 postal stations on the six great highroads starting from Bagdad. At some stations there were relays of horses, but in Syria and Arabia the messengers rode on camels; and in Persia the letters were conveyed from station to station by messengers on foot. The postal service under the Califs was an independent branch of the administration, and in addition to the conveyance of despatches and travellers was added the supervision of all the authorities in outlying possessions. Of the two classes of superior postal officers, the _nowaqquium_ was the postmaster who received the postal packets and letters and attended to their conveyance, whereas the _farwaneqqyun_ was a kind of chief postmaster at the capital of a province, who controlled the work of the postmasters and made his own report on all the civil and military authorities to the central office in Bagdad. These reports were so valuable that Calif Abu Djafar Manssur is credited with the statement: 'My throne rests on four pillars, and my power on four men--a blameless kazi (judge), an energetic chief of police, an honest minister of finance, and a faithful postmaster who gives me reliable information on everything.' It has been said that the Roman _cursus publicus_, the _frumentarii_, the _agentes in rebus_, and the _curiosi_ served a similar purpose, but the Arabian arrangement was more systematic. In the Post Office of the Califs the letters and packets posted, as well as those received from other places, were entered in special lists, where their number and address had to be stated. This practice was observed in India till a few years ago, and it will thus be seen that the letter bill of the modern posts was in use already among the Egyptians in 270 B.C., and also among the Arabs. From the information that has been preserved, it is inferred that the Arabian posts did, to a certain extent, transmit private letters, but this was not done officially, and the couriers and postmasters conveyed such correspondence, along with the official despatches, on their own account."--I. G. J. Hamilton, _Outline of Postal History_, Calcutta, 1910, p. 4. _Mexico_.