450 T. S. Ellin — Lou- Water Channela in Rivers and Eiduaries. 



the channel there. My reasoning was that the persistence of a shoal 

 in the mid-stream of a river constantly depositing and removing mud 

 indicated some need for a channel on both sides ; and having regard to 

 the line of the tide coming round Hooghly Point and going over to 

 the other side, where, as shown by the tongues in the shoal, it is 

 directed towards Ninan Creek ; having regard also to the main stream 

 which from Fulta Creek is directed downwards to the right side, 

 tributary streams seemed to be necessary to account for the persistent 

 channel on the left or eastern side of the shoal. Moreover, it appears 

 that the eastern gut, as it is called, does in the dry season, that is, 

 when there is no local water, partially close, when ships pass on the 

 western side. Thus, in suggesting that the supposed tributaries should 

 be intercepted and united in one channel brought out towards Hospital 

 Point, I did but suggest the perpetuation of conditions under which 

 this undesirable channel does tend to close. Every stream below 

 Ninan Creek should, as I suggested, be so diverted, and the eastern 

 gut be rendered unnecessary as a first step towards its extinction. 

 Then, in my view, the stream would pass from Ninan Creek over to 

 the right side, which is in the line of the tide as indicated by the 

 tongues in the shoal, and a single, continuous channel would be 

 assured. 



Mr. Vernon-Hai'court's proposal is to put a long training-wall, 

 extending from Fulta Point, into the shoal ; he ignored the tributaries 

 on the left side ; he did not in his printed plan indicate their existence. 

 Yet, being there, the creek between the proposed training-wall and 

 the shore could not possibly close. 



Fulta Point seems to illustrate a principle which I have long tried 

 to impress on friends concerned in the management of estates. The 

 margin of a river should be drained in a direction away from the 

 stream, and the drainage be brought into the river only at fixed points 

 as far apart as possible. Here the head of the stream is near the 

 margin of the river, and a permanent promontory has formed. The 

 formation of natural, raised banks, or levees as thej- are called on 

 the Mississippi, seems to be promoted by a division of the flood-water 

 as it recedes, part flowing into the river and part into the lateral 

 drainage, thus leaving a line comparatively free from current. 



Neither the map of a survey in 1851-5, to a scale of 1 inch to 

 a mile, nor a later one to a scale of 4 inches, show the tributaries 

 plainly. I am, however, satisfied that a complete map, taken with 

 the chart, would show that every part of the river might be classed 

 under one of these headings. 



A. No stream coming in on either side — a straight, well-defined 



channel. 



B. Streams coming in on one side only — a well-defined channel 



on that side only. 



C. Streams coming in on both sides — an ill-defined channel and 



a disposition to form a shoal in mid-stream. 

 I may add that of twenty-five engineers who took part in dis- 

 cussing Mr. Vernon-Harcourt's paper, many of them writing at great 

 length, not one seemed to recognize tributary streams as having any 

 influence at all in diverting the river-channel towards their outlets. 



