Thames Estuary Limits and Origin. 



From the aspect of geography and physics, probably the 

 west end of the estuary might best be regarded as the head of 

 Sea Reach, or as it merges into the Lower Hope near the 

 boundary stone of the Watermen's Company. Hereabouts the 

 shores more decidedly narrow, and this is where brackish water 

 becomes more sensibly evident, even at half-ebb. Thus the 

 change in temperature through the tidal mixture of fresh and 

 salt water here most truly denotes an estuarine character. 

 Moreover, the interests of estuary fishermen (notably those of 

 Leigh and Southend) extend thus far ; so practically for sea- 

 fishery purposes the natural west extension of the Thames 

 Estuary to the Lower Hope is preferable to that of Tizard or 

 of the Conservancy's limit. 



If the same principle of the physical geography with refer- 

 ence to the salinity and temperature of the water be taken 

 into account, then the eastern section of the Thames' mouth 

 say from the Nore or, perhaps, the Mouse Light, due south, 

 might be considered under the denomination of a firth,* as 

 holds good in the Forth, the Clyde and other northern rivers. 

 But, on the other hand, the term " Thames Estuary," par excel- 

 lence, has been applied for centuries by navigators, fishermen, 

 Government and other authorities to the area stretching from 

 between the North Foreland towards Harwich, and embracing 

 the exit of the rivers Medway, Crouch, Black water, Colne, 

 Stour and Orwell. Hence we may abide by the common defi- 

 nition Thames Estuary, irrespective of the scientific distinction 

 betwixt an estuary and a firth, or the minor inflowing rivers 

 above-mentioned. 



2. Estuary Origin. To obtain a retrospective view of this 

 estuarine question and its bearings on fisheries, a glance at the 

 geological evidence is instructive. In long past ages Kent 

 joined the continent of Europe, for then there were no Straits 

 of Dover. Most of the southern part of the North Sea was low, 

 flat, dry land. Through this ran a great river which drained 



* Sre Mill, "On River Entrances," Brit. Assoc. Rep. for 1886, and 6th Ann. Rep. 

 Fishery Board, Scotland, for 1886. 



