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28 one yields an abundance of metals, it not only gives back to the owner the money he has spent, but also gives a profit besides; certainly there will be for him rich and profitable mining, if of the whole number, three, or four, or more veins should yield metal. Very similar to this is the advice which Xenophon gave to the Athenians when they wished to prospect for new veins of silver without suffering loss. " There are," he said, " ten tribes of Athenians; if, therefore, the State assigned an equal number of slaves to each tribe, and the tribes participated equally in all the new veins, undoubtedly by this method, if a rich vein of silver were found by one tribe, whatever profit were made from it would assuredly be shared by the whole number. And if two, three, or four tribes, or even half the whole number find veins, their works would then become more profitable; and it is not " probable that the work of all the tribes will be disappointing " . Although this advice of Xenophon is full of prudence, there is no opportunity for it except in free and wealthy States; for those people who are under the authority of kings and princes, or are kept in subjection by tyranny, do not dare, without permission, to incur such expenditure; those who are endowed with little wealth and resources cannot do so on account of insufficient funds. Moreover, amongst our race it is not customary for Republics to have slaves whom they can hire out for the benefit of the people ; but, instead, nowadays those who are in authority administer the funds for mining in the name of the State, not unlike private individuals.

are now exhausted. The workmen, when the mines yielded a bad return to their labour, committed to the furnace the old refuse and scoria, and hence obtained very pure silver, for the former workmen had carried on the process in the furnace unskilfully."

Since 1860, the mines have been worked with some success by a French Company, thus carrying the mining history of this district over a period of twenty-seven centuries. The most excellent of many memoirs upon the mines at Laurion, not only for its critical, historical, and archaeological value, but also because of its author’s great insight into mining and metallurgy, is that of Edouard Ardaillon (Les Mines du Laurion dans I Antiquite. Paris, 1897). We have relied considerably upon this careful study for the following notes, and would refer others to it for a short bibliography on the subject. We would mention in passing that Augustus Boeckh’s " Silver Mines of Laurion," which is incorporated with his " Public Economy of Athens " (English Translation by Lewis, London, 1842) has been too much relied upon by English students. It is no doubt the product of one acquainted with written history, but without any special knowledge of the industry and it is based on no antiquarian research. The Mt. Laurion mining district is located near the southern end of the Attic Peninsula.

The deposits are silver-lead, and they occur along the contact between approximately horizontal limestones and slates. There are two principal beds of each, thus forming three principal contacts. The most metalliferous of these contacts are those at the base of the slates, the lowest contact of the series being the richest. The ore-bodies were most irregular, varying greatly in size, from a thin seam between schist planes, to very large bodies containing as much as 200,000 cubic metres. The ores are argentiferous galena, accompanied by considerable amounts of blende and pyrites, all oxidized near the surface. The ores worked by the Ancients appear to have been fairly rich in lead, for the discards worked in recent years by the French Company, and the pillars left behind, ran 8% to 10% lead. The ratio of silver was from 40 to go ounces per ton of lead. The upper contacts were exposed by erosion and could be entered by tunnels, but the lowest and most prolific contact line was only to be reached by shafts. The shafts were ordinarily from four to six feet square, and were undoubtedly cut by hammer and chisel; they were as much as 380 feet deep. In some cases long inclines for travelling roads join the vertical shafts in depth. The drives, whether tunnels or from shafts, were not level, but followed every caprice of the sinuous contact. They were from two to two and a half feet wide, often driven in parallels with cross-cuts between, in order to exploit every corner of the contact. The stoping of ore-bodies discovered was undertaken quite systematically, the methods depending in the main on the shape of the ore-body. If the body was large, its dimensions were first determined by drives, crosscuts, rises, and