It has been pointed out by Milchhoefer[232] that the mining district is considerably broken up by the Cleisthenic division of Attica into trittyes. Milchhoefer’s arrangement of the trittyes in the mining district has been convincingly simplified by Loeper[233], but Loeper himself leaves the mines divided between three trittyes of three different tribes. We may therefore still follow Milchhoefer in thinking that Cleisthenes took special precautions to break up this district. The same fact is noticed by Milchhoefer about the district round Plotheia, the Northern deme already noticed as belonging to the Epakria. Here too the Russian scholar has simplified, but here too only to a limited extent. “In a breaking up like this of the old hill country of the Peisistratids” Milchhoefer sees unmistakable signs of “measures directed against the Peisistratids.” Now that we have as good reason for seeing Peisistratan hill country round Laurium as round Plotheia, we must either reject Milchhoefer altogether, or, more probably, see in both districts centres of Peisistratan influence, of which the Southernmost was the more important. Mining operations in antiquity were conducted on a large scale. Forty thousand workers were employed in mines near Carthagena[234]. Athenaeus[235] speaks of tens of thousands of chained slaves as working in the Laurium mines and losing their lives in an unsuccessful revolt at the time of the second slave war in Sicily (103–99 B.C.). Of the 20,000 who deserted to Decelea when it was occupied by the Spartans in 413 B.C. it is not unlikely that large numbers were miners from Laurium[236]. But what was the state of the Laurium district in the days of Peisistratus? [Sidenote: The mines were almost certainly in full work at this period,] The mines of Laurium do not appear in history till 484 B.C.[237], when Themistocles persuaded the Athenians to devote the profits from them to the building of a navy. The _Constitution of Athens_ speaks of a discovery of mines in that year. This however is probably rather loose language. The writer’s words are “on the discovery of the mines at Maronea.” The “discovery” of 484 B.C. was of the mines in this particular part of the Laurium district, or rather, in all probability, of an extraordinarily rich vein in this particular part. “The disposition of the strata” (at Maronea) “is such that the richest are not those that could be first reached.... Some centuries of search and effort were therefore necessary in order to suspect their existence and to reach their level” (_i.e._ of the rich veins “discovered” in 484)[238]. [Illustration: Fig. 5. Corinthian terra cotta tablet depicting a miner at work.]