Changes in regional agricultural orientation split apart the A-Type and P-Type centroids of marriage seasonality in Figure 3.12. Agricultural specialization would have disrupted locally sustained tendencies towards balance between local supplies of, and demand for, agricultural labour. Regions becoming more arable, like East Anglia, would have experienced labour shortages. Its rural industry declined, just as the cloth-making of Hertfordshire had declined as the county became more arable in the sixteenth century. Regions turning from the production of grain to rearing, like the west, would have found themselves with labour surpluses, driving down local wages and attracting rural industry; John argued that while agricultural wages increased in the south and east after 1660, they were stationary in the west, and Bowden found agricultural wages substantially higher in arable than in pastoral regions in 1640–1750. Agricultural changes thus fed the fires of industrial volatility: there was a strong spatial association in the later seventeenth and early eighteenth centuries between newly pastoral (formerly arable) and newly industrial (also formerly arable) places, most notably in the Midlands and the West Country.