The supply curve is shown by a+b, indicating that goods are produced under conditions of increasing cost.
However, all points on the supply curve will have a coefficient of elasticity greater than one.
This is shown in the supply curve in Figure 9.
If there is an increase in demand, then prices will go higher causing a movement along the supply curve.
Dupuit, however, did not include a supply curve in his theory.
This is represented by the vertical distance between the two supply curves.
If, however, the authorities were to control interest rates, the supply curve might become downward sloping.
The article only describes a supply curve and that large open country can affect prices.
This is also the reason why "a monopoly does not have a supply curve".
The locus of these points would not be a supply curve in any conventional sense.