The Wealth of Nations by Part 4 Chapter 5 Page 62

These first owners either immediately supply the consumers in their own neighbourhood, or they supply other inland dealers who supply those consumers. The inland dealers in corn, therefore, including both the farmer and the baker, are necessarily more numerous than the dealers in any other commodity, and their dispersed situation renders it altogether impossible for them to enter into any general combination. If in a year of scarcity, therefore, any of them should find that he had a good deal more corn upon hand than, at the current price, he could hope to dispose of before the end of the season, he would never think of keeping up this price to his own loss, and to the sole benefit of his rivals and competitors, but would immediately lower it, in order to get rid of his corn before the new crop began to come in.