308 TRANSACTIONS OF THE CANADIAN INSTITUTE. [Voy. VIII. 
fe In order to make clear in one of its phases the relationships between 
quantity, wealth and value, I ask attention to the accompanying diagram. 
Let us assume that a quantity of water varies, as the line AG, from 
drought to deluge. At A there is absolute drought; from E to 
F satiety; from F to G there is excess and at Gdeluge. Let EC represent 
the quantity that is just sufficient to supply the wants of the community. 
When the quantity diminishes to LM, and labour is required to make good 
the deficiency, the water acquires a value, represented by LP. As the 
quantity falls to NO, more labour is required, therefore the value increases 
rapidly to NQ, and towards A the point of absolute drought, the value 
advances towards infinity AH; for, all that a man hath will he give for 
his life. 
From E to F the variation is so slight as to make no appreciable 
difference in utility or value. 
From F as the quantity becomes increasingly excessive towards 
G, more and more effort will be demanded in the way of drainage and 
otherwise, not to get a supply of a beneficent agent, but to get rid of a 
destructive agent. Therefore, there will come a negative value, increasing 
as the curve DVXK, varying negatively from zero to infinity. (Jevens 
Pp. 137-) 
The variation of value will, therefore, be represented by the curve 
HOCXK, varying from infinity + to zero, and then to infinity —. 
Let us now trace out the variation of wealth. At the point A, where 
there is absolute dearth, it is quite evident there is no wealth. Also at 
the point B, where the deluge is wholly destructive, there is no wealth. 
From the point A to E there is increase of wealth, and from T to B there 
is diminution. 
To trace the variation of wealth from the point A to E it is necessary 
to observe the variation of utility as a quantity increases from dearth to 
satiety. Jevons says, ‘‘A quart of water per day has the high utility of sav- 
ing a person from dying in the most distressing manner. Several gallons 
may possess much utility for such purposes as cooking and washing; but 
after an adequate supply is secured for these uses, any additional quantity 
is a matter of comparative indifference.” ... “It is clear then that 
utility is not proportional to commodity.’’ (Jevens p. 47.) 
It is quite evident, therefore, that any increment from A to O has 
greater utility than the increment from M to E. The curve of wealth 
therefore will diverge upward from AO and will converge to ME and will 
therefore form a curve in the direction AQE. In a similar manner the 
