512 



FOURTH REPORT — 1S34. 



Summary Table of the Day Tides, 



Showing the greatest and the least tides in March, April, and 

 May, 1832, 1833, and 1834, at New London Bridge. 



In the first year none of the lower portions of Old London 

 Bridge, (with the exception of two piers,) which prevented the 

 natural flow of the tidal w.aters, were removed ; and in the se- 

 cond year almost the whole of that structure was cleared away 

 as regarded the masonry and starlings, although the section of 

 the river was far from being completed ; many portions still re- 

 maining one or two feet above low-water mark, and which were 

 finally removed in the year 1834. 



In conclusion, it may be stated, — That the drainage of the 

 districts bordering on the river Thames has been greatly im- 

 proved ; — that barges, which used formerly to be towed up from 

 Putney to Richmond by horses, are now carried by the current 

 from London Bridge to Richmond in one tide ; — That the fall 

 of the low-water surface heloiv Bridge has been so considerable 

 as to cause ships, in many instances, to ground in their tiers at 

 low-water ; — and that from a register of the tides, kept by Capt. 

 Maugham of the London Docks, the average depth at low-water 

 on the cill of Shad well Dock was 1 ft. 10 in. below the Old Tri- 

 nity datum ; and that where formerly there were 8 feet in depth 

 upon the Dock cill, there are now only 6 feet 2 inches on the 

 average : on the 51h of November, 1834, the tide fell as low as 

 4 feet 3 inches on the cill. 



The accompanying Plate shows the section of the river Thames, 

 from actual survey, from the mouth of the river Kennet to the 

 Nore. The upper part could not be taken in time. 



* During equinoctial gales in March, wind N.W., but the average rise barely 

 exceeded six inches above Trinity datum. 



