HISTORICAL. 89 



valley of the Walbrook, bounded on the west by the Fleet valley 

 and on the east by comparatively low ground. Here was a 

 ' square mile ' of dry healthy soil with a good water supply 

 obtainable from shallow wells. From here adequate watch 

 could for the first time be kept over traffic coming up the Thames ; 

 here, the mouths of the Walbrook (Dowgate) and the Fleet pro- 

 vided good ports and the steep bank of the latter a good defence ; 

 from here a road ran on dry gravel soil to Hyde Park Corner and 

 diverted much of the traffic using the Westminster ford. 



In late Roman times, therefore, we find a great walled City 

 of London and a small isolated settlement at Westminster, and 

 this state of things continued for centuries ; in Domesday Book, 

 Westminster is a small village. London remained practically 

 confined by the walls till the end of mediaeval times, when the 

 need for a defence on the west became less urgent. It should 

 be noted that the hill facing the river is now less steep than the 

 natural bank which lies some 60 ft. north of the northern side 

 of Thames Street ; the intervening area, about 45 acres in 

 extent, has been formed by successive encroachments on the 

 River. 



Westminster owed its importance to the Abbey and the 

 Royal palace, the latter first built by Cnut. It remained small 

 in extent, and the nucleus of Thorney Island can still be recog- 

 nised in a map of Commonwealth date. It became linked up 

 with London, through the village of Charing by a growth 

 along the ' Strand,' where the gravel impinges on the river. 

 As late as 1578 Agas's map shows only a line of great houses, 

 such as the Savoy, facing the river, mean houses along the north 

 side of the road, and then open fields, including the Convent 

 (Covent) Garden. With the Restoration, an era of rapid expan- 

 sion set in, and the gravel area between the Tyburn and Fleet 

 was completely built over by the end of the 17th century. The 

 northward limit of the gravel then became the limit of the town ; 

 the water supply was still from the Thames in its immediate 

 neighbourhood and from the gravel by springs or wells elsewhere. 

 The conduit system for bringing water from distant springs, as 

 at Tyburn, Paddington and Hackney, had been developed as far 

 as possible (p. 82). The clay areas could not be built upon 

 before the beginning of the 19th century, when iron pipes and 

 steam pumps came into use. Till then the spread of bare London 

 Clay around North London was waste land ; parts of the original 

 forest remained, such as St. John's Wood. The railway termini 

 from Paddington to King's Cross mark what was for a hundred 

 years the outskirts of London. 



The surrounding villages were also built upon water-bearing 

 strata ; Chelsea, Battersea and Bermondsey grew up on eyots of 

 gravel near the river; Kensington, Paddington, Acton, Baling, 

 Islington and Highbury on the north, Putney, Roehampton, 

 Clapham, Balham, Tooting, Brixton and others on the south, all 



