Resort has also been had to aqueducts, and these represent some of the best work that British canal engineers have done. The first in England was the one built at Barton by James Brindley to carry the Bridgewater Canal over the Irwell. It was superseded by a swing aqueduct in 1893, to meet the requirements of the Manchester Ship Canal. But the finest examples are those presented by the aqueducts of Chirk and Pontcysyllte on the Ellesmere Canal in North Wales, now forming part of the Shropshire Union Canal. Each was the work of Telford, and the two have been aptly described as "among the boldest efforts of human invention of modern times." The Chirk aqueduct (710 feet long) carries the canal over the River Ceriog. It was completed in 1801 and cost £20,898. The Pontcysyllte aqueduct, of which a photograph is given as a frontispiece, carries the canal in a cast-iron trough a distance of 1,007 feet across the valley of the River Dee. It was opened for traffic in 1803, and involved an outlay of £47,000. Another canal aqueduct worthy of mention is that which was constructed by Rennie in 1796, at a cost of £48,000, to carry the Lancaster Canal over the River Lune. These facts must surely convince everyone who is in any way open to conviction of the enormous difference between canal construction as carried on in bygone days in Great Britain--involving as it did all these costly, elaborate, and even formidable engineering works--and the building of canals, or the canalisation of rivers, on the flat surfaces of Holland, Belgium, and Northern Germany. Reviewing--even thus inadequately--the work that had been already done, one ceases to wonder that, when the railways began to establish themselves in this country, the canal companies of that day regarded with despair the idea of practically doing the greater part of their work over again, in order to carry on an apparently hopeless struggle with a powerful competitor who had evidently come not only to stay but to win. It is not surprising, after all, that many of them thought it better to exploit the enemy by inducing or forcing him to buy them out! The average reader who may not hitherto have studied the question so completely as I am here seeking to do, will also begin by this time to understand what the resuscitation of the British canal system might involve in the way of expense. The initial purchase--presumably on fair and equitable terms--would in itself cost much more than is supposed even by the average expert. "Assuming," says one authority, Mr Thwaite, "that 3,500 miles of the canal system were purchasable at two-thirds of their original cost of construction, say £2,350 per mile of length, then the capital required would be £8,225,000."