(2) When the Supply, instead of being absolutely limited, can only be increased with difficulty or after the lapse of time, similar but less extreme results will be observed. Let us suppose, that pianos are selling in some rural community at $300 each, that there are twenty persons in the place who want a piano immediately, that there are but fifteen pianos on hand, and that the number cannot be increased for half a year. The market-rate will certainly rise above $300. How much above? To that point, at which only fifteen of the twenty will be willing to purchase at the new rate. The equation of Supply and Demand will be reached by a rising rate which cuts off five competitors. This is the principle, working only roughly in practice through the estimates and good judgment of dealers and purchasers. A better illustration of this second class of cases is, perhaps, the Grains and other agricultural products. When these have been gathered, there is no more home supply for a year; and any deficiency in the crops will raise their market-rate, not at all in the ratio of the deficiency, but according to the relations of the diminished Supply to a new Demand. Since the abolition of the Corn-Laws in England in 1846, and the resulting ease of grain-imports from abroad, a deficiency of home crops has no such effect on the price of cereals as it had before that time; when, according to Tooke's History of Prices, an expected falling-off of one third in the crops often doubled and sometimes quadrupled the usual prices; which shows that the world ought to become one country in respect to all food supplies, as indeed happily it is now for the most part, each country allowing them to be distributed freely everywhere in accordance with this law of Demand and Supply. Speculation is more busy in grain, in cotton, and in such things generally, because a new Supply can only be had once a year; early information is eagerly sought at the trade centres in regard to the prospects of the growing crops, and has its influence one way or the other on current prices; but the world is so wide and all the parts of it now so closely connected together by steamship and telegraph, that the prices of the great food staples are remarkably uniform over the earth, and Speculation has not the chance it once had to count and "corner." (3) In the only remaining and by far most comprehensive class of cases, in which the Supply of Commodities and Services and Credits can be readily and indefinitely increased to meet enhanced Demand, and easily withdrawn from market and stored when Demand declines, each rise and fall of market-rate tends to be speedily checked through the mere action of Supply; and the doubly and harmoniously working Law but just now referred to keeps Value in this class of cases comparatively steady all over the world.