Herodotus: Ἱστορίαι – Histories
Godley's Loeb translation is available in HTML format from the Perseus Project and in various scanned formats from the Internet Archive. Other earlier translations are also available online, for anyone who wants to look.

Herodotus, trans. A. D. Godley (1920) The Persian Wars (4 vols). Cambridge, Mass; London: Harvard University Press; Heinemann. http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3atext%3a1999.01.0126
 Herodotus, trans. A. D. Godley (1920) The Persian Wars (4 vols). Cambridge, Mass; London: Harvard University Press; Heinemann. [Scanned]
    Vol I (Bks I, II)   2 (III, IV)   3 (V–VII)   4 (VIII, IX)