46 miles of canals - all underground!

He became known as the "Canal Duke", or "Canal Maker" because after the Bridgewater Canal was opened, it was followed by similar projects throughout the country.

The Duke had inherited the mines of Worsley in 1748, and after his proposal of marriage had been accepted and then rejected by the beautiful Duchess of Hamilton, with injured pride he left the high society of London to examine the business potential of his inheritance.

By 1757 the Duke realised that little improvement had been made in the mines since 1600. The amount of coal got from the mines was small, and the method of transporting it, by horse and cart, was antiquated. However, there was as yet no alternative.

The Duke had spent much of his youth travelling on the Continent, and had seen the canals of France and Italy. He realised that if he could drive a canal direct from his mines in Worsley to the markets in Manchester, he would considerably reduce the transport costs of his coal, and therefore to the population.

The problem of water in his mines at the time was becoming serious, and the Duke sent for James Brindley, an ingenious millwright employed at Clifton where he had done some excellent work in draining mines by his invention of the famous water wheel driven by the River Irwell, and used to pump water from the flooded colliery.

At about the same time Thomas Gilbert, agent for Lord Gower, the Duke's brother in-law, asked John Gilbert, his brother, to inspect the mines at Worsley. Gilbert immediately realised the value that coal mines would have if a canal could be dug. Plans were prepared, were passed by the House of Commons, and the Bridgewater Canal Act received Royal Assent in March, 1759.

Work on the surface canal started at once under the supervision of James Brindley, while Gilbert paid more attention to the Duke's other undertakings and the development of the coal mines. It was not all straight forward, of course. The original line had to be altered because of constructional difficulties, such as the inability of the engineers to beat the bogs of Chat Moss. Then there was the construction of the aqueduct across the Irwell at Barton Bridge, the extension of the canal from Manchester through Cheshire to link up with the Mersey, the Leigh Branch, and finally the link-up by the Leeds and Liverpool canal, which enabled excursions to be run from Manchester to the Lake District, as well as to Liverpool and a point near Southport.

Perhaps the most remarkable part of the whole construction, though, was the underground canal. Almost as soon as work began above ground, work also began on driving a tunnel northwards towards the sandstone face of Worsley Delph. The mines were worked as near to the underground canals as possible, and the coal dragged in baskets to the boats. The workings moved east and west along the strike of the seams, and canal arms were tunnelled at right angles to the main underground canal sometimes as far as a mile.

Beside the main level, as it was called, there were three other canals at different levels. These would carry coal from the workings to a suitable shaft where the coal would be hoisted and loaded into boats in the main level. From Worsley the land rises northwards to Walkden and Farnworth, and the mine workings in those areas were well above the main level of the canal. To solve this problem, coal was lowered from the higher levels by means of an inclined plane, the long, narrow barges riding on iron frames operated by hand-winches.

The main level of the underground canal was continued northwards to Dixon Green at Farnworth, then turning west to Morris Green and almost as far as St Helens Road, Bolton. In all, there were almost 46 miles of underground canals as part of the system, the majority of which were in what is now the Bolton Metropolitan Borough.

But as coal was worked out, the branch lines fell into disuse, and the last coal was brought out from the underground canals in about 1890, although after that the system was used to carry away water drained from collieries along its "banks". The disused canals are still there, but all that can be seen is the entrance tunnel at Worsley.

The third Duke of Bridgewater died in 1803, aged 67, never having married. Towards the end of his life he was described by his sister in law as having "a want of religion", explaining that she did not mean that he did not believe in God, but "here he is with gout and a disorder in his stomach, and death and immortality never occupy his thoughts or words". And, she added, "He swears".

Before his death, though, the Duke created a Trust to administer his estates, coal mines and canals. The Bridgewater Trustees sold the canal in 1872 to the Bridgewater Navigation Company for £1,115,000, and in 1885 the Manchester Ship Canal Company bought it for £1,710,000. The steel turning aqueduct over the Manchester Ship Canal, itself a marvel of engineering, was constructed about 1890 to replace Brindley's stone one, which obstructed traffic on the Ship Canal.

It is an intriguing story of how the Duke and the engineering genius James Brindley linked great industrial centres by water, carrying canals not only underground, but over river and road, on their unique system. They never lost confidence in their remarkable task which resulted as a reaction to the Duke's unsuccessful love affair.

The Duke is said to have spent nearly a quarter of a million pounds on his great canal ventures, which later brought him an annual income of £80,000. But the reward was small compared with his simple joy in bringing cheap coal to the poor. What wealth his canals created in Lancashire cannot be estimated.