Each seller, as we have seen, has in mind a minimum price under which he cannot go without sustaining a loss. Accordingly, each of the sellers of bicycles - seven, let us say, with one bicycle each - who attends our assumed bicycle auction has settled on the lowest price he will take for his bicycle. As in the case of the buyers we can represent the sellers by letters, as R, S, T, U, V, W, Z. Also we can attach minimum prices to each of them as follows: R - 17, S - 18, T - 20, U - 23, V - 28, W - 31, Z - 40. In the preceding section it was noted that we could not determine the number of bicycles demanded until the market price was fixed. A similar difficulty exists in the determination of the available supply, since, according to our assumption, those sellers whose minimum price exceeds the market price will withdraw their bicycles from the auction. Fig. 4 illustrates graphically the character of the various demands; Fig. 5 of the various supplies.