These foraging expeditions of the boys prepared them for the similar, if more arduous, duties of “Secret Service”[37] which awaited them between eighteen and twenty. Young men of this age were sent in bands to the different districts of Laconia for long periods, during which they hid in the woods, slept on the ground, attended to their own wants without a servant, and wandered about the country by day and night.[38] When it appeared good to them or their chiefs they made sudden attacks on the Helots, and slaughtered those who seemed ambitious enough to be dangerous, the Ephors declaring war on their serfs yearly in order that there might be no blood-guiltiness attached to these assassinations.[39] There was a regular officer set over this secret police, who no doubt directed where the particular youths should go.[40] At a critical moment of the Peloponnesian War, 2000 of the bravest and most ambitious Helots suddenly “disappeared,” probably by this means.[41] But Plato recognised the educational value of such a system, if the murders were omitted. In his _Laws_[42] he institutes a force of κρυπτοί [kryptoi], 720 in number, who patrol the whole country, taking the twelve districts in turn, so as to gain a complete acquaintance with it. They have all the farm-servants and beasts at their disposal, for digging trenches, making fortifications, roads, embankments, and reservoirs, for irrigation works and the like. The similarity of name suggests similarity of functions, but how much of this the κρυπτοί [kryptoi] at Sparta did cannot be fixed. Probably their chief work was to keep watch over the subject populations, Perioikoi and Helots, who were otherwise left almost entirely to their own devices. In their institutions of the foraging parties and Secret Service, the Spartans show a clear appreciation of boy-nature, as well as a keen eye for methods of military training. Moderns are beginning to realise that the average boy has so much of the primitive and natural man in him that, unless he is permitted to “go wild” and live the savage life at intervals, he is apt to become riotous and lawless. Hence in recent days the institution of camps for boys in England and “Seton Indians” in America. The Spartans, alone of Hellenes, fully recognised this peculiarity of boys, and met it with the foraging expeditions and secret service. The Athenian boy was not thus provided for until he became an ephebos; hence the Athenian streets were full of young Hooligans, while the aristocratic lads developed more refined, if more vicious, methods of giving vent to their instincts. In these country-expeditions alone the Spartan boys had an opportunity of escaping from the presence of their elders and developing habits of self-reliance and responsibility. Had Sparta made better use of these opportunities, the fate of her Empire after Aigospotamoi might have been different.