CHAP. VII.

NEW WORKING OF MINES.

175

which might prove detrimental to the workingof those in the continental dominions of theempire. Notwithstanding the severe regulationsunder which these persons held their lands, theywere not strictly speaking slaves. They wereallowed to dispose of their property if they couldfind purchasers ; but as the new possessors wereto be bound to the same services, and were to beplaced under the same restrictions, as the formerholders, it does not seem probable that it couldhave been easy to meet with such purchasers.Besides these, who were a kind of feudal tenants,slaves were employed in the imperial mines.They were not indeed foreigners, who had beenstolen by piracy and sold, but criminals, whohad been condemned by the laws to slavery.

From the earliest period of Roman history,under the consuls and the dictators, labourin the mines had been adopted and practisedas a punishment in many cases; but underthe emperors it was so much extended, that itbecame as universally the penalty inflicted onoffenders against the laws as under the ancientkings of Egypt . This mode of providing forthe working of the mines seems to have beenscarcely adequate to the providing of labourersfor such of them as were already in operation,a od utterly insufficient for opening the new®ines which had been acquired by conquest onthe banks of the Danube . Hence the emperors