Of this policy, the economic result was to carry still further the depression of Italian agriculture. The corn supplied at low rates or given away by the administration was of course bought or taken in the cheapest markets--those of Sardinia and Sicily, Egypt, Africa, and Gaul--and importation once begun would be carried to the utmost lengths of commercialism. Italian farms, especially those at a distance from the capital,[194] could not compete with the provinces save by still further substituting large slave-tilled farms for small holdings, and grinding still harder the face of the slave. When finally Augustus,[195] definitely establishing the system of lowered prices and doles, subsidised the trade in the produce of conquered Egypt to feed his populace, and thus still further promoted the importation of the cheapest foreign grain, the agriculture of a large part of Italy, and even of parts of some provinces, was practically destroyed. It has been argued by M'Culloch (_Treatises and Essays: History of Commerce_, 2nd ed. p. 287, _note_) that it is impossible that the mere importation of the corn required to feed the populace--say a million quarters or more--could have ruined the agriculture of Italy. This expresses a misconception of what took place. The doles were not universal, and the emperors naturally preferred to limit themselves as far as possible to paying premiums for the importation and cheap sale of corn. (Cp. Suetonius, _Claudius_, c. 19, and the Digest, iii, 4, 1; xiv, i, 1, 20; xlvii, ix, 3, 8; l, v, 3, etc.) All of the conquered provinces, practically, had to pay a tithe of their produce; and where corn was specially cheap it would be likely to come to Rome in that form. (Cp. Dureau de la Malle, _Écon. polit. des Romains_, ii, 424 _sq._) Many of the patrician families, besides, owned great estates in Africa, and they would receive their revenues in produce. Egyptian, Sardinian, Sicilian, and African corn could thus easily undersell Italian for ordinary consumption. For the rest, the produce of Egypt would be a means of special revenue to the emperor. Cp. M'Culloch's own statement, p. 291.