He was angry with himself, and angry with Megabates, and angry with Artaphernes. He presumed, too, that Megabates would denounce him to Artaphernes, and, through him, to Darius, as the cause of the failure of the expedition. A sudden order might come at any moment, directing that he should be beheaded. He began to consider the expediency of revolting from the Persian power, and making common cause with the Greeks against Darius. The danger of such a step was scarcely less than that of remaining as he was. While he was pondering these momentous questions in his mind, he was led suddenly to a decision by a very singular circumstance, the proper explaining of which requires the story to return, for a time, to Histiæus at Susa.
Histiæus was very ill at ease in the possession of his forced elevation and grandeur at Susa. He enjoyed great distinction there, it is true, and a life of ease and luxury, but he wished for independence and authority. He was, accordingly, very desirous to get back to his former sphere of activity and power in Asia Minor. After revolving in his mind the various plans which occurred to him for accomplishing this purpose, he at last decided on inducing Aristagoras to revolt in Ionia, and then attempting to persuade Darius to send him on to quell the revolt. When once in Asia Minor, he would join the rebellion, and bid Darius defiance.
The first thing to be done was to contrive some safe and secret way to communicate with Aristagoras. This he effected in the following manner: There was a man in his court who was afflicted with some malady of the eyes. Histiæus told him that if he would put himself under _his_ charge he could effect a cure. It would be necessary, he said, that the man should have his head shaved and scarified; that is, punctured with a sharp instrument, previously dipped in some medicinal compound. Then, after some further applications should have been made, it would be necessary for the patient to go to Ionia, in Asia Minor, where there was a physician who would complete the cure.
The patient consented to this proposal. The head was shaved, and Histiæus, while pretending to scarify it, pricked into the skin--as sailors tattoo anchors on their arms--by means of a needle and a species of ink which had probably no great medicinal virtue, the words of a letter to Aristagoras, in which he communicated to him fully, though very concisely, the particulars of his plan. He urged Aristagoras to revolt, and promised that, if he would do so, he would come on, himself, as soon as possible, and, under pretense of marching to suppress the rebellion, he would really join and aid it.