HOPPER DREDGES.

Evening Star, Issue 5170, 30 September 1879, Page 3

HOPPER DREDGES.

We have been shown the illustrations of the hopper-dredger [Neptune, working at Newhaveu, England, th« working results for dredging and carrying two miles being about lid per bn, noirly 100 per cent, less than by the system adopted at Lyttelton of having a fixed dredger and two steam hoppers attending on her. Wo recommend the members of the Haibor Board to examine the ' Engineer of Augiißt 8 on the Athenteum table, in which is given the fullest explanation of the working of this latest improvement in dredging. For the benefit of those of our readers who are interested in harbor improvement and have not the opportunity of seeing the papers, we may say that the l»eptune has been at work for three months at Newhaven, and has more than answered the expectations of her builders. The engineer describes her performances in the way of lifting and discharging material as greater thin have been done before at the same cost. Her length is 145 ft, breadth 32ft, depth_l3£ft, and her hopper hold contains about 550 tons of soil. The dredging-gear and its chain of buckets can bo traversed forward in advance of the bow, which is so formed as to enable it, when required, to cut the vessel's own flotation through shoals, bars, and sandbanks. The buckets are capable of raising 300 tons per hour, and of loading the hopper cavity in less than two hours, and when at constant work the entire consumption of coal is about one ton of coal per load of 500 tons raised and deposited. The entire crew consists of ten hands ; and the coat per ton of mud raised and deposited is 1.35 d. Messrs Simons and Co., the builders of the Neptune, in a letter to a gentleman in this town, contrast her work with that of the dredge employed in Lyttelton harbor. They say : " W r e find that the expenditure in salaries alone in the stationary dredger Er*kine and its two hopper tenders is L 4.275; and for fuel, stores, and repairs, L 2.755 ; or a total of L 7.030 for twelve months. Now our patent hopper dredge Neptune, doing about an equal amount of work at the port of Newhaven, Sussex, does not exceed for its entire working expenses (at your Colonhl rates) L 3.500 per annum, or half that of the Erskine system."