Why did Cambridge grow?

This may seem an obvious question, but it relates to a specific street, in fact two or three streets in Cambridge, which were built in the first decades of the nineteenth century. These houses look too small to be connected with the university, and they predate the railway. Why were they built?

The houses I am referring to are in Park Street and Lower Park Street, at the southern end of Jesus Green. Here is Lower Park Street:

 They were built in the first decades of the nineteenth century, as far as I can see. They are not singled out for mention by Pevsner (in his volume on Cambridgeshire), although Pevsner perversely admires the multi-storey concrete car park around the corner, dating from 1972. But leaving aside the elderly Pevsner's questionable taste, there remains the question: why so many early nineteenth-century artisan cottages in Cambridge?

A possible answer was suggested in Peter Bryan's Cambridge: The Shaping of the City (revised edition 2008). In this interesting book, seemingly published by the author himself, Bryan devotes a chapter to the expansion of Cambridge in the nineteenth century. The reasons he gives are:

• parliamentary enclosures 1802-1811, enabling land to be bought and sold;
• an increase in population due to general improvements in health;
• the process of industrialisation
• the coming of the railway - although since this only arrived in Cambridge in 1845, it is unlikely to be the reason why Lower Park Street was built.

Whatever the case, the houses in Lower Park Street have a lovely simplicity, yes, helped by the uniform plot of grass outside each house, that makes them memorable - far more memorable than the multi-storey car park.