39

in the theory of value and prices.

9.

nIn v

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10 .

tank* and free to move only vertically (being so constrained by atelescope arrangement beneath and not shown in the diagram).

A glance at fig. 8 or fig.

10 (a plan of fig. 8) willshow that any right andleft row of cisterns is rela-tive to a single individualand corresponds to fig. 6and that any front and backrow is relative to a singlecommodity and correspondsto fig. 4.

The water in these cis-terns must be subjected totwo sets of conditions, first:the sum of all the contentsof IA, IIA, 1IIA, etc., shallbe a given amount (viz:the whole of the commod-ity A consumed during the_given period) with a like given sum for the B row, C row, etc.,secondly: the sum of 1A, IB, IC, etc., each multiplied by a coeffi-cient (the price of A, of B, of C, etc.), shall be given (viz: thewhole income of I during the period) with a like given sum fo? the

11 row, III row, etc.

* The level of water in each cistern is intended to be that of the level in thetank. The only constant cause which will make the levels different is the differ-ence between the weight of the whole cistern and the weight of the water dis-placed by its walls (partly wood) which difference is slight, may be plus orminus, and is equal to the weight of the excess or deficit of water in the cisternabove or below the outside level.