I LOVED Dava Sobel's Longitude. In the same scientific vein, Simon Winchester could do for the history of geology what she did for horology with The Map That Changed The World: The Tale of William Smith and the Birth of a Science (Viking £12.99). It's the story of "Strata Smith", his quest to map the rocks of England and to understand the meaning of their distribution and layers.

William Smith was born in 1769. His father was a village blacksmith and skilled mechanic who died suddenly from a chill when William was but eight years old. The boy was sent to live with a neighbouring uncle and worked on his farm.

This was in a part of Oxfordshire where curious bun-shape stones would, and still do, turn up in fields - Oxfordshire pound stones or Chedworth buns.

As they were remarkably uniform, nearly all weighing in at 22oz, dairymaids used them as weights on butter scales - the butter was sold as a "long pound". These stones fascinated the boy. Their resemblance to sea urchins had already been noted but their presence in Oxfordshire certainly sparked the imagination and curiosity of young Smith.

William was to make his name and his living at first as a surveyor for mining and canal interests. Then he worked freelance, turning his hand to almost anything, surveying, advising on field drainage, prospecting for coal, shoring up coastal defences, repairing Bath's hot springs or building a mill.

He knew his soils and was renowned for knowing what was underneath. He was also renowned for his continuous learning. When travelling by stage coach, he would sit up with the driver, never in the shelter of the carriage, always making notes, drawing, even stopping the coach to leap off and chisel away a piece of rock. Lacking personal funds, he needed patronage and this certainly helped his early studies but unfortunately William liked to live beyond his means.

During the early 1800s, he concentrated his efforts on mapping the British Isles. Others were becoming interested in geology in these, its early stages, and in 1807 a Geological Society was formed. Unfortunately for Smith, he lacked "gentleman" status and the aristo-centric society kept him out while blatantly plagiarising his work, and eventually undercutting the price of his precious map when it was printed in 1815 with their own, copied, map.

Smith was financially ruined and spent 80 days in debtors' prison. On his release, he left London on the overnight stage and arrived in Northallerton three days later, with some of his equipment, his mad wife, and a nephew.

The next seven years were spent travelling around the North, odd-jobbing, lecturing, surveying for drainage, lecturing, making the odd visit to London, keeping in touch with friends and contacts, and importantly, still always learning. He became fond of Scarborough, making it his base.

In 1820 Scarborough Corporation employed him to improve the town's water supply. In 1821 he published his Geological Map of Yorkshire, and then he helped set up the geological museum in the rotunda in Scarborough.

In 1828 he got something of a break. Through Philosophical Society meetings in Scarborough, he met Sir John Johnstone of Hackness Hall. In 1828, Sir John offered him a job as land steward, giving him the vicarage (now a hotel) to live in. Sir John was one of the more enlightened members of the Geological Society. The "old guard" were losing control to a new breed of scientists who accorded as much honour to the practical men as to the theorists and thinkers.

Hackness was literally put on the map by Smith being there, geologists regularly visited him and by 1826 the question of recognising his contribution to geology was raised.

Eventually William Smith received his long-overdue society membership and was the first person to be awarded its new, prestigious Wollaston medal in 1831.

In 1834, Smith moved backed to Scarborough, this time to his own cottage and garden, leaving behind him at Hackness a beautiful map of the estate which still hangs at Hackness Hall. His Geological Map of the British Isles hangs behind blue curtains on the stairs of the Geological Society.

He died in 1839 after catching a chill