This traces back to Charles Davenant and Gregory King's early
formulation on the effect on corn prices of a "defect in the supply of
corn." Their little table showed that
A defect in the supply of 1/10 (caused) an increase in the price of 3/10
A defect in the supply of 2/10 (caused) an increase in the price of 8/10
A defect in the supply of 3/10 (caused) an increase in the price of 16/10
etc.
This table shows up in any number of early sources -- especially
Thomas Took's *High and Low Prices* etc.
Jim Henderson