As the expansion or contraction of the circulating medium is thus an agent of such prodigious power and irresistible weight, both upon the fortunes of particular states and the general progress of the species, so it will be found upon examination that it is by a withholding or letting loose the fertilising flood, that Providence appears often to act most directly and decisively upon human affairs. When a nation has performed its mission, and is to make room for other actors on the great stage of the world, if its power has rendered conquest by a foreign enemy impossible, a contraction of its domestic currency paralyses its internal strength, and renders dissolution, at no distant period, a matter of certainty. If a great start is prepared for human industry, if new continents are laid open to its energies, and an unusual impulse communicated to its activity by the development of social and democratic passions, a vast addition is suddenly made to its metallic resources, and the increased numbers or enhanced efforts of mankind are amply sustained by the newly opened treasures of the reserves of nature. Rome, impregnable to the assaults of undisciplined barbarians, yielded, at the appointed season, to the contraction of its domestic currency, which rendered the maintenance of armaments adequate to the public defence a matter of impossibility in the later days of the empire; and when the discovery of the compass, of the art of printing, and of the new hemisphere, had at once given a vast impulse to European activity, and provided new and boundless fields for its exertion, the mines of Potosi and Mexico were suddenly thrown open, and nature provided a suitable reward for all this enhanced effort by the continually rising price of its produce.