Next consider an increase in supply. Suppose farmers have better weather, for example, causing more crops at the harvest. Or suppose there is discovery of huge new oil reserves underground. Or suppose a new invention, such as Eli Whitney’s cotton gin, increases the production of a good (cotton). This curve shows what happens when there is an increase in supply: | Next consider an increase in supply. Suppose farmers have better weather, for example, causing more crops at the harvest. Or suppose there is discovery of huge new oil reserves underground. Or suppose a new invention, such as Eli Whitney’s cotton gin, increases the production of a good (cotton). This curve shows what happens when there is an increase in supply: |