A first class map

Here's a cricketing puzzle that's got me stumped.

England has about 39 counties or shires, or maybe that should be 42, or maybe even 46, an interestingly vague number unlike the unimaginative precision of the 50 American states...but the English taste for vagueness is not what this post is about. However one chooses to count, 18 adds up to less then half the English counties. Yet, only 18 counties (the darker coloured counties on the map above) play first class cricket. How did this come to pass?

For instance, Shropshire, that fabled land where the Empress of Blandings covered herself with such glory, would surely have a deep rooted cricketing culture? Or consider Lincolnshire, a well-populated county wedged in between the cricketing powerhouses of Yorkshire and Nottinghamshire. Surely Lincolnshire would be able to muster a decent county team? Club cricket is played in both Shropshire and Lincolnshire. But both seem content to remain Minor Counties, without objecting to the condescension loaded into that term.

Even more mysterious, Durham, the current champions, are the only Minor County to have been promoted to the first class level in 80+ years. This was a one time "historic" event. There is no mechanism by which the top Minor Counties get promoted to the first class level, and the weakest first class counties get relegated to the minors.

This instinctively feels odd to me, as an Indian cricket fan, because the growth of cricket outside India's traditional metropolitan centers is one of the most fascinating changes in Indian cricket over the last 25 years.