The New York James Farley Post Office Motto comes from Ancient Persia?

The building prominently bears the inscription: Neither snow nor rain nor heat nor gloom of night stays these couriers from the swift completion of their appointed rounds, which is frequently mistaken as an official motto [1] of the United States Postal Service [2]. It was actually supplied by William Mitchell Kendall of the firm of McKim, Mead & White [3], the architects who designed the Farley Building and the original Pennsylvania Station in the same Beaux-Arts style [4]. The sentence is taken from Herodotus [5]' Histories [6] (Book 8, Ch. 98) and describes the faithful service of the Persian [7] system of mounted postal messengers under Xerxes I of Persia [8]. The USPS does not actually have an official motto or creed, but nonetheless the inscription on the building is universally recognized as such.

http://en.wikipedia.org/wiki/James_Farley_Post_Office [9]