River Thames shipping coming in and out of London, in 1732 it received the world's first lightship. This became a major landmark, and was used as an assembly point for shipping. Today it is marked by Sea Reach No. 1 Buoy. The River Thames contains over 80 islands ranging from the large estuarial marshlands of the Isle of Sheppey and Canvey Island to small tree-covered islets like Rose Isle in Oxfordshire and Headpile Eyot in Berkshire. They are found all the way from the Isle of Sheppey in Kent to Fiddler's Island in Oxfordshire. Some of the largest inland islands, for example
Estuary English more widely spoken in parts of Sussex, Hampshire, Bedfordshire, Berkshire, Buckinghamshire and Middlesex as well. Estuary English shares many features with Cockney, and there is some debate among linguists as to where Cockney speech ends and Estuary English begins. The variety first came to public prominence in an article by David Rosewarne in the "Times Educational Supplement" in October 1984. Rosewarne argued that it may eventually replace Received Pronunciation in the southeast. Studies have indicated that Estuary English is not a single coherent form of English; rather, it has some of the phonetic features of working-class London speech spreading at