Reciprocal obligations imposed upon Athens, in case Argos, Mantineia, or Elis, shall be attacked. Neither of the four contracting powers shall grant passage to troops through their own territory, or the territory of allies over whom they may at the time be exercising command, either by land or sea, unless upon joint resolution.[78] [78] Thucyd. v, 48. καὶ τῶν ξυμμάχων ~ὧν ἂν ἄρχουσιν~ ἕκαστοι. The tense and phrase here deserve notice, as contrasted with the phrase in the former part of the treaty—τῶν ξυμμάχων ὧν ~ἄρχουσιν~ ἑκάτεροι. The clause imposing actual obligation to hinder the passage of troops, required to be left open for application to the actual time. In case auxiliary troops shall be required and sent under this treaty, the city sending shall furnish their maintenance for the space of thirty days, from the day of their entrance upon the territory of the city requiring. Should their services be needed for a longer period, the city requiring shall furnish their maintenance, at the rate of three Æginæan oboli for each hoplite, light-armed or archer, and of one Æginæan drachma or six oboli for each horseman, per day. The city requiring shall possess the command, so long as the service required shall be in her territory. But if any expedition shall be undertaken by joint resolution, then the command shall be shared equally between all. Such were the substantive conditions of the new alliance. Provision was then made for the oaths,—by whom? where? when? in what words? how often? they were to be taken. Athens was to swear on behalf of herself and her allies; but Argos, Elis, and Mantineia, with their respective allies, were to swear by separate cities. The oaths were to be renewed every four years; by Athens, within thirty days before each Olympic festival, at Argos, Elis, and Mantineia; by these three cities, at Athens, ten days before each festival of the greater Panathenæa. “The words of the treaty of peace and alliance, and the oaths sworn, shall be engraven on stone columns, and put up in the temples of each of the four cities; and also upon a brazen column, to be put up by joint cost at Olympia, for the festival now approaching.” “The four cities may, by joint consent, make any change they please in the provisions of this treaty, without violating their oaths.”[79] [79] Thucyd. v, 47.