170 



REPORT 1878. 



river channel and bar were not also deepened to correspond. Sixty- 

 years since the depth of water on Dublin bar was about 6 feet ; indeed, 

 there was, a few years ago, an old man in the harbour employment who 

 had in his youth stood on the bar at a good low water. At this time the 

 North Bull Wall did not exist, and the bar, consisting of hard sand, 

 extended in a curved direction about half a mile east of Poolbeg Light- 

 house. As soon, however, as the Bull Wall was built, the large volume 

 of water flowing and ebbing over the 2500 acres which were enclosed 

 between it and the Pigeon House Wall, was confined in direction and 

 augmented in velocity, so that it impinged against the bar and scoured 

 it away to its present depth of about 16 feet at low water, giving a depth 

 of 28 feet at high water springs, and this is still gradually improving ; 

 for 20 years since there was 3 feet less than at present, and it is believed 

 that there is no other instance on record of a bar being so successfully 

 deepened by artificial means. The depth in the river channel has 

 recently made great progress, corresponding to the other improvements 

 in the port. The average tonnage dredged in each of the ten years 

 preceding 1860 did not reach 150,000 tons, and it is now close on a 

 million tons per annum. The greater portion of this dredged material is 

 now conveyed to sea in very large hopper barges, each of which carries 

 850 to 1000 tons, according to the state of the weather, to a distance of 

 8 miles from Dublin, or about 2 miles beyond the Bailey Lighthouse, 

 where it is deposited in deep water beyond the influence of tides within 

 the bay. Very great economy has resulted from this system of large 

 hopper barges as compared with the older methods ; for, multiplying 

 the present tonnage dredged by the saving per ton, the gross saving 

 amounts to considerably over 40,000Z. per annum. Indeed, without this 

 economy it would have been impossible to carry out the other improve- 

 ments in the port ; for Dublin, though one of the larger ports in the 

 kingdom, has relatively the smallest income, as there are no dues on 

 goods except some small ones on timber, bricks and marble, which in 

 the aggregate do not reach 2000Z. annually. This will appear at a 

 glance from the following table, which gives the revenue derived by the 

 ports already mentioned from tonnage dues and dues on goods for the 

 year 1877, and also the income which each ton yields the several ports as 

 well as their respective debts. 



The rates on goods for Liverpool include the so-called " Town dues " 

 on goods, amounting to 263,3292. ; but as these were purchased by the 

 Mersey Docks and Harbour Board from the Corporation of Liverpool in 

 1857 for their then estimated value of a million and a half sterling, they 

 now form a very valuable portion of the port revenues. 



