There is one thing which, it may seem, I have overlooked, in attributing these industrial depressions to the speculative advance of rent or land values as a main and primary cause. The operation of such a cause, though it may be rapid, must be progressive—resembling a pressure, not a blow. But these industrial depressions seem to come suddenly—they have, at their beginning, the character of a paroxysm, followed by a comparative lethargy, as if of exhaustion. Everything seems to be going on as usual, commerce and industry vigorous and expanding, when suddenly there comes a shock, as of a thunderbolt out of a clear sky—a bank breaks, a great manufacturer or merchant fails, and, as if a blow had thrilled through the entire industrial organization, failure succeeds failure, and on every side workmen are discharged from employment, and capital shrinks into profitless security. Let me explain what I think to be the reason of this: To do so, we must take into account the manner in which exchanges are made, for it is by exchanges that all the varied forms of industry are linked together into one mutually related and interdependent organization. To enable exchanges to be made between producers far removed by space and time, large stocks must be kept in store and in transit, and this, as I have already explained, I take to be the great function of capital, in addition to that of supplying tools and seed. These exchanges are, perhaps necessarily, largely made upon credit—that is to say, the advance upon one side is made before the return is received on the other. Now, without stopping to inquire as to the causes, it is manifest that these advances are, as a rule, from the more highly organized and later developed industries to the more fundamental. The West Coast African, for instance, who exchanges palm oil and cocoanuts for gaudy calico and Birmingham idols, gets his return immediately; the English merchant, on the contrary, has to lay out of his goods a long while before he gets his returns. The farmer can sell his crop as soon as it is harvested, and for cash; the great manufacturer must keep a large stock, send his goods long distances to agents, and, generally, sell on time. Thus, as advances and credits are generally from what we may call the secondary, to what we may call the primary industries, it follows that any check to production which proceeds from the latter will not immediately manifest itself in the former. The system of advances and credits constitutes, as it were, an elastic connection, which will give considerably before breaking, but which, when it breaks, will break with a snap.