We have noticed already that the principal towns grew naturally on the banks of the rivers. There is a further fact about their situation which we may observe, and that is that the chief and largest of them were placed just so far up the rivers that they might get best advantage from the tide. In days long before steam was used to drive ships, and when they could {113} sail only with the wind very much in their favour, you can easily understand how valuable the help of the tide would be, both for coming up and going down a river. Then, if the town were placed just above the point up to which the saltish sea-water came, the fresh water coming down could be used for drinking and for such processes as brewing and tanning hides which were very early industries; and there would be a constant flow of water to work the corn-grinding mills. Considerations of that kind probably influenced the Anglo-Saxons in choosing sites for their towns such as Canterbury, and Winchester, and London, which became the capital after the Norman conquest. From the Continent people could cross the Straits of Dover and find themselves very soon in the sheltered waters of the Thames estuary or of the Stour which went past Canterbury. The land about the mouth of the Stour has risen a good deal since those days, and the passage of ships up the river was more open and wide then than it is now. The advantage of Winchester, as a site for a large town, was that from the mouth of the Seine, which came down past Rouen, a very short sea-passage would bring the mariner into the sheltered water behind the Isle of Wight. He could enter that shelter from the east or from the west, as the wind served best, and he would be out of sight of land, either French land or English land, for only a very short distance in the mid-crossing. This was a matter of much importance to the sailors of those days; they did not at all like to go out of sight of their landmarks. Then, once in the Solent, as we call it, the shipman would take advantage of the tide to carry him up Southampton Water, and very likely some way up the Itchen river, towards Winchester, before he need run his ship aground and disembark. {114} As a further advantage you may see that both Canterbury and Winchester had high ground close about them on which a fortified camp could be made for the protection of the town. And we know, in fact, that such camps were made in the vicinity of both towns. The ground bears signs of them to this day. The beginnings of London are thought to have been a British hill fort on the hill where St. Paul's Cathedral now stands. Of other cities we know that Manchester was a British settlement and a place where the Druids worshipped, and later a Roman city. We hear of Birmingham as a village of the Saxon Beormingas. Liverpool was a fishing village in Saxon times, but not of sufficient importance to be named in Domesday Book.