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be termed, torpedo-boat catcher, although it is no use for the purpose this name would denote, and, in fact, is too slow for many purposes, yet has its uses and its value at times. The destroyers and the torpedo-boats in their several ways were able to demonstrate their respective sea-keeping capabilities. Finally a writer says, "These manoeuvres should teach us clearly that no enemy is to be despised, that victory is not always to the swift, and that we are yet some way from that standard of strength which will give us security."

Portsmouth Dockyard.

The mobilization and other matters have made a busy time in this yard, but their Lordships appear to be entirely satisfied with the progress made. We are rather proud of the turnout of the Sultan and Inflexible, two vessels which have undergone considerable repair and alteration. The Sultan, on her speed trial, made 14 knots, and the Inflexible from 12.5 to 13 knots, which says a good deal for the machinery, and looks as if these will be valuable ships for some time to come. According to present arrangements the Prince George battleship will commence her steam trials very early in September. It is confidently expected that she will be the next ship of the Majestic class to be commissioned. The Channel Fleet ships in hand are to be away again by the end of the second week in September. The Malabar troopship, paid off here some months ago, has been commissioned as a coal hulk at Bermuda. The stern torpedotubes are to be taken out of all the ships of the Royal Sovereign class, so that these vessels will now only carry submerged tubes, and it is thought probable that this will be the rule in modern construction. It is pretty much of a race now between the Prince George and the Victorious, and so far we are well ahead, although the Prince George was not laid down until three months after the Chatham ship. This yard scored, however, because when there was some delay in the delivery of guns and armour, the Admiralty ordered that which was for the Victorious to be delivered at Portsmouth. All the heavy guns of the Prince George were on board before the end of July, and as the authorities ordered overtime to be worked both on this vessel and the Cæsar, no doubt they want to get them completed. The Caesar will be floated out in October, but will take at least a twelvemonth after that to get her ready for the Fleet Reserve. Do what they will it is not likely the Caesar will make a record. The Gladiator cruiser is making slow progress, and therefore it seems likely that the Canopus will not be begun this year. Her engines are to be built by Messrs. Scott & Co., of Greenock. The Iphigenia and Indefatigable are being made here for the pennant and will go to Australia. The Nelson has been commissioned at last and will be missed from the yard. The Manning of the Navy.

Discussion on this important subject has been given an impetus by the controversies created by Lord Charles Beresford's lecture at Liverpool. His Lordship, it will be remembered, began by explaining that he was not making an attack upon the Admiralty, but because Mr. Goschen has not at once accepted his proposals, a bitter agitation has been begun which is in effect a most determined attack on the authorities. It is necessary to acquit Lord Charles Beresford of any part in this attack, he has merely supplied the ammunition and retired from the field to Norway, leaving his secretary to act as commander-in-chief of the forces. As to the gravamen of the charge it is this: Lord Charles in his figures makes out that so far as men in the regular service are concerned and including 11,200 for the new ships now building, there is a total deficiency of 27,562, including 5,000 engine-room ratings. It is unnecessary to enter into the question of whether these figures are exact or not, for it is generally admitted that there is a deficiency, and the official scheme for supplying it is by a steady and continuous increase of ratings. Any other plan, as has been pointed out by more than one writer of weight, will not only disarrange all the present facilities for accommodation, but will lessen the opportunities for training in the case of the men already in the service. Lord Charles Beresford admitted that there was no hurry, it is only his followers who have discovered that hasty legislation is necessary. considered apart from the requirements of the Regular service there is the Reserve, and recently arrangements have been made for giving this force further and better training than was formerly the case. Some of the Reserve men are being engaged for fixed periods, and will thus obtain a knowledge of life on board a man. of-war. Altogether the Reserve may be said to be improving. But Lord Charles Beresford wants to introduce a short service

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scheme of his own, which is to supply a temporary number of active service men, provide a reserve, and raise the status of the Mercantile Marine at one swoop. He would enter 5,000 men for a service of five years in the Navy, with a subsequent retaining fee as a first-class Reserve, and other 5,000 men each year to have two months' training, of which one afloat, as a second-class Reserve, thus securing 30,000 men at an estimated cost of £600,000. Extending the system over eleven years he would hope to secure 70,000 men at a total cost of £3,740,000, or adding the cost of training, of £1,440,000 a year. His Lordship would like to see 15,000 men entered next year, 5,000 Marines, 5,000 first Reserve men, and 5,000 regulars to make up for waste. By this scheme he hopes to make the Navy a nursery for the Mercantile Marine, and to see all subsidised vessels carry Reserve

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To say that the activity with which the year began still continues at this yard is a commonplace to all who have paid it a visit. Certainly no one can walk round the docks and ships without being impressed with the busy aspect of everything. Of the vessels in hand the Victorious is making rapid progress towards completion. Three of the heavy guns have been mounted, and it is anticipated that the remaining one will be on board and her trials begin early in September. The military tops and platforms are complete masts fitted with signalling apparatus, and the gun shields on board. The Illustrious would have made more progress had it not been for the delay in the delivery of armour plates. It is still hoped that she will be fit for floating in November next. As soon as possible the Goliath battleship will be begun on the slip from which the Victorious was launched. The Leander and Arethusa are both in hand here, the latter being fitted with a quick-firing arrangement. Some little work there has been in connection with the torpedo-boat destroyers which are to be sent out of Portsmouth as tenders to ships in the Mediterranean and China. The basins are now full of ships, but several of these are on the point of commissioning. Of new cruisers the Minerva is now out of the hands of the Chief Constructor, and the Vindictive is being pushed forward in her place. The cruiser Endymion has been prepared for relief service here, and has left for Malta with new crew for the Hawke. The Northampton, boys' sea-going training ship, was also in hand for a short time, and has now left for another recruiting cruise. The Venus, built by the Fairfield Co., was delivered here some weeks ago, and is now to be taken in hand for fitting; her trials have been very successful. The men are now being sent back to the Vindictive, but she is behind time, just as the Minerva is behind her sisters the Eclipse and Talbot. The cause of the mishap to the crown plates of her boilers is said to have been facing the fires too hastily without sufficient time for the plates to expand. The Tribune is being prepared here for service in Australia.

The "Powerful" and "Terrible."

The contractor's trials of the Terrible came to an untimely end owing to defects in the machinery, and long before any attempt had been made to develop the full specified H.P. The cause of the defect is variously stated, one report stating that it was due to an insufficient allowance for the expansion which always follows alternate applications of heat and cold to the metal used in the construction of the machinery. It is also said to have been caused by the circumstance that the intermediate cylinders of the Terrible are fitted with flat slide valves instead of those of cylindrical shape, and that the relief or vacuum rings of these valves got out of order, and under the steam pressure the valves broke down, Whatever the cause no blame is to be attached to the boilers. While the necessary alterations are being made in the Terrible, her sister ship will be tried. The Powerful was undocked on July 19th at Portsmouth, having been sheathed with copper, had her under-water fittings examined, and her submerged torpedo tubes fitted on board. Most of the mountings for her 6-in. guns were in place, but in neither this vessel nor the Terrible have the 9-2-in. guns, which are to be worked with electric motors, yet been mounted. A new method for arranging the screw propellers by these cruisers is being tried. In nearly all our men-of-war the twinscrews are so arranged that when the engines are moving ahead the screws turn outwards from the line of keel. In these cruisers the reverse is the case. It has been feared that this plan might adversely affect their steering qualities, but this has not yet been found to be so, in fact, the steering of the Terrible through

the fleet at Spithead was noticed by onlookers as a splendid exhibition of handling a big ship. The trials of the Powerful will take place as soon as those of the Prince George, which are to begin September 7th, are completed, and it is estimated these will take at least a fortnight. The Powerful will make a first run of not less than thirty hours duration at 5,000 I.H. P. for the purpose of ascertaining the coal consumption at this power, and another run will follow for the same purpose, but at 18,000 H.P., and then if these runs are satisfactory, the vessel will be steamed for four hours at the full specified H.P. of 25,000. After this a further run, but of only four hours, will be made with 22,000 I.H.P. It is anticipated that the Duke and Duchess of York will proceed to Australia in either the Powerful or Terrible, escorted by the Blake and Blenheim.

Devonport and Keyham Yards.

Although the selection of Sir Edmund Freemantle as the successor of Sir Algernon Lyons was rather in the nature of a surprise, since it was well-known that Sir Edmund's wishes were in the direction of the Mediterranean, he is making a most popular Commander-in-Chief, and at the same time keeps the port booming. The report that the Renown would be com. missioned for the manoevures did not meet with much credit here, as it is well known that mobilization knocks the gingerbread off a ship a good deal, and Sir John Fisher will want to hoist his flag on a spic and span vessel. Seeing that this vessel only came round from Pembroke last November, that sbe is ready for sea is very creditable to the yard. Now the Arrogant has been launched the only ship under construction here is the Furious, her sister, laid down in June last year, she will be ready to leave the slip during the ensuing month. The Talbot has been commissioned to relieve the Magicienne in the West Indies, and this takes the pride of the yard away. It would pay the authorities well to order another Talbot right away. The reconstruction of No. 3 slip has been begun, and it is hoped that the keel plate of the Ocean will be laid here on December 28th. The engine for this vessel will be made by Messrs. Hawthorn, Leslie & Co. The last chapter in the naval manoeuvres is the paying off of the vessels after mobilization, but the number of ships to hoist the pennant here being small, this has not made a great deal of work one way or the other in the yard. The Aurora is to be taken in hand here for service on the China station, and the Sirius for a commission in Australasian waters. A scheme has received official sanction which will have the effect of doing away with the powder magazine vessels above Saltash Bridge. New storehouses have been erected at Ball Point and the substitution of cordite for powder makes it less dangerous to house these stores on shore.

The Commemoration of Trafalgar.

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On July 20th the secretary of the Navy League wrote circular letter to most of the daily papers in this country and the colonies, proposing that throughout the Empire on October 21st next, the battle of Trafalgar, which assured to us maritime supremacy and commercial prosperity, shall be commemorated by decorating the statues of the great Admiral and in other ways. This proposal for a public celebration of Trafalgar day has in the popular phrase "caught on," and is being taken up with enthusiasm in mary quarters. As last year the Nelson Column in Trafalgar Square is to be decorated, and it is hoped that the Naval authorities will consent to provide a guard of honour of bluejackets for the occasion. Lord Drogheda is in hopes that the Admiralty will order a naval review in Hyde Park, in which case it is suggested that the men should be publicly entertained. There are to be thanksgiving services at various cathedrals, and great efforts are being made through municipal bodies to stir up general interest in the celebration. Anything tending to make our countrymen familiar with what the Navy has done, and what we must depend upon it to do, cannot fail to be useful, and the Navy League is therefore to be commended for the good work it has in hand. Trafalgar was the crown and completion of a long series of operations, many of which were carried out by men who had died before Nelson was born, and it is quite as necessary to impress this on the public mind as to do homage to the great Admiral. In this connection we note that Professor Laughton has in the press an illustrated memorial volume of the life and death of Nelson, entitled, "Nelson and his companions in arms." The work will give concise biographical and historical accounts of Nelson's life, times and companions in arms. It will contain over fifty illustrations in photogravure, half-tone and line, including about thirty auto

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As usual the manoeuvres have brought this yard a great deal of small refitting. I must not, however, include in this category the Landrail, where a good deal of new work had to be executed. Overtime was at first worked on her, but this was soon found unnecessary, and she will now be ready again for service by the second week in September. The Swallow, paid off here at the end of July, is to be prepared for another three years commisssion, and it seems likely that she will take the place of the Dolphin in this year's programme. The general idea is that she is to be used for the training service. The Speedy has been in hand for small defects, and the Blenheim and Charybdis, also of the Channel Fleet, have been here to give leave, and as usual have wanted a little doing before they leave for Malta as escort for the destroyers and torpedo-boats going out there. The Wye has taken her departure, and she is so often here that we are bound to miss her. Several changes have also taken place in the flotilla of torpedo-boat destroyers owing to some going abroad, and this delicate piece of mechanism require frequent looking after. The trials of the Pelorus are expected to commence about September 15th, and will attract considerable attention not only at the first of a type, but because she is supplied with watertube boilers. Her machinery was built by Messrs. J. & G. Thomson, Clydebank, and it is estimated she will develop 7,000 H.P. at forced draught and make 20 knot speed. Under natural draught her engines are to indicate 5,000 H.P., which should give her a speed of 18-5 knots. The Pelorus has made good progress towards completion. The Proserpine, her sister ship, represents all the building now going on here. She is to be launched before the end of the year. The Dolphin, Barracouta, and Gleaner are all expected here for refit, and now that the Egeria is finished off we shall be glad of them.

Our Fleets on Foreign Stations.

Much has been accomplished of late years in the way of increasing our forces on foreign stations, but still more remains to be done in this direction. It is more than ever necessary that our seamen should have training at sea, and that as we increase in personnel we should place more ships in commission in which officers and men can gain the essential experience. Moreover, we have to recollect that other nations have not been standing still. Russia has now a very large and strong force in the Pacific, the fleets of the United States are more powerful than they were a few years back, and many of the smaller foreign Powers have augmented their navies. The British Mediterranean fleet is now stronger than it has ever been before, the Particular service squadron having joined in, so that three British Admirals' flags are now flying in these waters. There are now twelve battleships in commission in the Mediterranean, which is not one too many, there are also twelve cruisers, a proportion which would have to be doubled in war time. Hitherto, there has only been one destroyer, the Ardent, attached to the Ramillies, but now four more are to be dispatched to the station, and will be allotted as follows: the Banshee to the Nile, the Boxer to the Trafalgar, the Bruiser to the Hood, and the Dragon to the Barfleur. On the China station a gradual increase of force has been made by sending heavier ships to the relief of older or less powerful vessels. A further change is to be made in this direction by the substitution of the Aurora for the Porpoise. Two destroyers, the Handy and Hart, are also to be sent to this station to be attached, when they arrive, to the Centurion and Grafton. In the North America and West Indies station, the substitution of the Talbot for the Magicienne is an increase of power, and no doubt further changes here will be carried out shortly, as at present the newer ships are few in number. On the Australian station also, the four cruisers of the Katoomba class at present there will be relieved by the Indefatigable, Iphigenia, Tribune and Sirius. The former, when they come home, will probably be employed as drill ships for the R.N. Reserve, and it is understood that one of them will be stationed at Bristol. It is in contemplation to attach all the drill ships to the flag of the Admiral Superintendent of Reserves, and like the gunboats which have recently been made coastguard tenders, to call out all these vessels annually for sea service during the manoeuvres. At home it is to be noted that not only is the Channel Squadron now more powerful and more

numerous than it has ever been before, but a very large number of effective vessels, including destroyers, are employed in the training service, and are virtually in commission for active service.

Pembroke Dockyard.

It was originally the intention of the Chief Constructor to begin the work of sheathing and coppering the Adromeda early in August, but a delay has taken place and now it is more likely to be commenced in September. Whenever it is practicable to begin plenty of men will be put on, and the job expedited as much as possible. The tug Storm Cock, which has for many years been employed in connection with this yard, has now been taken away for service at Malta and is to be permanently stationed in the Mediterranean. The last of the armour plates of the barbettes of the Hannibal have been placed in position and secured. The work was done very smartly and creditably. According to the Naval Estimates the only vessel to be laid down in this yard is a cruiser similar to the Andromeda, but preparations are now being made to build another Hannibal on No. 5 slip, while the cruiser will be built on No. 1 slip after the Andromeda is launched.

Channel Fleet Inspection.

Although there was no naval review in honour of Li Hung Chang, as it was at one time thought would be the case, au opportunity was afforded the great Chinese statesman for seeing some of our finest vessels. At the same time the return of the Channel Squadron, augmented as it had been for the manoeuvres, to Spithead was utilised to parade the fleet before the Queen; and Her Majesty, the Prince and Princess of Wales, and other less notable personages, made a tour of the ships on subsequent days. The arrival of the fleet was made the opportunity for a splendid display of seamanship, the vessels passing Osborne in single file, and then turning back to Spithead, assuminga fourline formation in which they anchored simultaneously. On Wednesday Lord Walter Kerr made a signal from the Majestic: "I am desired by the Queen to express to the fleet her pleasure at the appearance of the ships on the occasion of her visit to Spithead on Tuesday." The Prince of Wales also, on concluding his inspection on Wednesday, signalled from the yacht: "I am much gratified with reception and the magnificent appearance of the fleet." The fleet was indeed a magnificent one, and well worthy of the encomiums of royalty. There have been greater gatherings of vessels in the historic anchorages, but no fleet has ever anchored there which excelled the one under the command of Admirals Lord Walter Kerr and Armand Poulett in homogeneity and composition, and the modern character of its component parts. Altogether the spectacle afforded the visitors-for in addition to her Majesty and his Royal Highness the Prince of Wales, Li Hung Chang, a party of members of Parliament, and many other sightseers made a tour of the fleet-was full of interest and instruction.

Navy Employment Agency.

I am asked to call attention to a work that is being entered upon by a new association called the Navy Employment Agency. The purpose is to secure employment on shore for time-expired men of the Navy and Marines of good character. The agency is conducted by a committee of the Castaways' Club, a dining club composed entirely of naval officers who have resigned their commissions, but who wish in this way to show their continued interest in the service to which they belonged. The agency should become a useful means of communication between employer and the unemployed, and the former will do well to write to Commander Ernest Kinder, R.N., of Craig's Court, Charing Cross, the secretary of the agency. None but men of thoroughly good character are entered on the books, and not only do bluejackets make excellent servants, but in these days of motor care, &c., good drivers in plenty should be obtained from this source, for the engine-room complement is not forgotten.

Sir Christopher Furness, Westgarth & Co., Limited, have acquired the businesses of Westgarth, English & Co., and of the Tees Side Iron and Engine Works Co., Limited (except so far as the Bridge Building and Blast Furnaces are concerned), from 1st July, 1896. The new company take over all current trade contracts, and will carry on the business.

LAUNCH OF H.M.

TORPEDO-BOAT

DESTROYER, "STAR."

ON August 11th Her Majesty's torpedo-boat destroyer Star,

was launched from the Howdon yard of the Palmer Shipbuilding and Iron Co., Limited. The vessel is the first of eight of the same class which are being built by the Jarrow firm for Her Majesty's Navy. Her dimensions are:-Length, 215 ft.: breadth, 20 ft. 9 in.; and the displacement is about 300 tons. Her armament consists of one 12-pounder quick-firing gun forward on the conning tower, with four six-pounder quickfiring guns on the broadside, and one six-pounder on a platform aft. There are also two revolving torpedo tubes on deck, arranged to fire on either broadside. The builders have guaranteed a speed of 30 knots per hour, and the machinery, which has been designed by them, consists of two sets of triple-expansion engines, steam being supplied by four of Reed's pate t water-tube boilers. The christening ceremony was gracefully performed by Mrs. Cleveland, wife of Admiral Cleveland, one of the directors of the Palmer Co. Amongst those present were Admiral and Miss Cleveland, Mr. and Mrs. J. D. Milburn, Mr. and Mrs. A. M. Palmer, Mr. John Hall, Mr. and Mrs. F. S. Newall, Mr. and Mrs. Spicer, Mr. Sclater, Mr. and Mrs. Charlton, Mr. and Mrs. Redmayne, Mr. Norman Redmayne, Mr. M. Dodd and Miss Dodd, Messrs. Absey and Matthews (Admiralty overseers), Mr. H. Rowell, Miss Morey, Mr. and Mrs. Snowball Innes, Mr. S. Ramsay, Mr. C. J. Potter, Mr. J. P. Wilson, and Mr. and Mrs. P. A. Berkley. After the launch, those present adjourned to the offices.

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As will be seen from Figs. 1 and 2 of the accompanying illustrations, the patent shackle is very much less cumbrous than the present form of shackle, the former being in fact, as regards its shape and size, practically identical with any other link in the chain. in which it is to be employed, thus allowing it to work with perfect ease and safety over the windlass, or capstan, while it travels as freely and smoothly through hawse pipes, stoppers, etc., as any other part of the cable can do.

The patent shackle is as easily connected and disconnected as the ordinary shackle, and its use does away with all enlarged end, and intermediate links,

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and as each of Rae's shackles is made of special steel and tested far beyond the regulation strain, and supplied with Board of Trade certificate to that effect, it follows that they can be used as emergency" links, and the cable put into use at once without the trouble and expense of having to send it home for re-passing by the Board of Trade, and thus a cable need not be invalidated.

The patent shackle is built up, as shown in Fig. 3, of five parts, each made of special steel, the whole when fitted being held together by the collar, of specially hard steel, which passing through the centre is secured by a transverse pin and leaden pellet in the ordinary way. The centrepiece and the two half-links are, as it were, dovetailed into one another, so as to bring the strain on to the shoulders thus formed in the different parts instead of on to the collar.

furnace horizontal multitubular donkey boiler. The shafting and other forgings are all of iron; the boilers are of steel, with iron tubes.

Submergence. On Tuesday, 24th December, 1895, this steamer, carrying a cargo of about 650 tons of "burnt ore "" from Irvine to the Tyne, struck on a 1ock in the Sound of Mull, and was at once beached in Scallaster Bay, where the sea stood a little over her after-deck at low water, and close up to her bridge deck at high water. On the following Monday, 30th December, after having been submerged six days, she was pumped out and raised. On the same day steam was got up in the main boiler; but when about 30 lbs. pressure had been reached, the steam valve on the donkey pump blew out, and it was found that the copper at the bend of the donkey feed-pipe next the main boiler had disappeared; fires were therefore drawn, and the boiler blown off. Friday, 30th January, 1896, all leaks having been so far reduced as to be under control of the salvage pumps, the vessel left in tow for Belfast, where she arrived early on Saturday morning, all the salvage operations having been successfully conducted by Capt. Bachelor, of the Liverpool Salvage Association. Cause of Corrosion.-On examination the machinery was found

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On

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FIG. 1.

We were shown samples of these shackles which had been proved to even beyond the breaking strain of the cable; they were designed for use with and beyond a slight elongation. The ease with which they could be connected and disconnected had suffered no diminution, in fact, it is more than probable that every link in the cable would have given out before the shackle.

UNUSUAL CORROSION OF MARINE
MACHINERY.*

BY MR. HECTOR MACCOLL, OF BELFAST.

CORROSI

NORROSION in Marine Engines and Boilers is usually confined to well-known parts, is not rapid in its action, and may be prevented or stopped by the adoption of suitable measures. In a recent instance its action was so wide-spread, so rapid, and so powerful, as to render a short description of it somewhat interesting to engineers.

Steamer.-The steamer Glenarm is a steel vessel of the long raised quarterdeck type, built in Belfast in 1890 for the Antrim Iron Ore Co.; and is engaged in their trade between Belfast and ports on the north-east coasts of Scotland and England. She is classed 100 A1 in Lloyd's register, with a deadweight capacity of about 800 tons; and her machinery consists of three-crank triple engines with cylinders 17 in., 27 in. and 44 in. diameter by 30 in. stroke, a three-furnace single-ended boiler of the usual type loaded to a pressure of 165 lbs. per square inch, and a single

Read at the Summer Meeting of the Institution of Mechanical Engineers in Belfast.

FIG. 2.

to present an extraordinary appearance: all wrought-iron work was deeply and roughly corroded, and planed cast-iron work rendered so soft as to be easily cut with a knife. These unusual effects were undoubtedly caused by the cargo of "burnt ore"; and the following explanation has been contributed by Mr. S. Courtney, chemist, of Messrs. Francis Ritchie & Sons, Belfast, who investigated the subject at the request of Mr. Robert Browne, secretary and manager of the Antrim Iron Ore Co. "Burnt ore is the residue from the manufacture of vitriol from sulphur pyrites, and is generally found to contain about 4 per cent. of sulphate of copper, together with a little sulphate of iron due to the sulphur not having been completely burnt out of the ore and becoming oxidized into sulphates. The sulphate of copper would be more or less completely dissolved in sea water; and as the latter contains a considerable quantity of chloride of sodium or common salt, this would re-act on the sulphate of copper, forming sulphate of sodium and chloride of copper. The sulphate of copper and chloride of copper are both soluble in water; and a solution of either, or both, dissolves wrought-iron and cast-iron. The chloride is more energetic in its action than the sulphate; but in time a solution of either, no matter how weak, will dissolve an atom of iron for every atom of copper present. Every hundred tons of cargo contained as much sulphate of copper as would, if available, dissolve nearly 32 cwts. of metallic iron. The burnt ore might also contain a small quantity of free sulphuric acid, which would combine with the soda of common salt in the sea water, and set free hydrochloric acid; and the latter would rapidly act upon copper or brass."

Extent of Corrosion.-On the condition of affairs being discovered, the engines and boilers, as well as the hull, were at once opened up for survey, the underwriters being represented by Mr. Henry H. West, of Liverpool, and the owners by Mr. James Maxton, of Belfast; the entire work on the hull and machinery was afterwards carried out under the direction of the latter. The general condition of the engines was that wrought-iron work had been penetrated by corrosion to a depth of about 3-32nds in.,

and planed cast-iron so softened that 1-8th in. had to be taken off before a hard surface was regained. Surfaces in bearing contact, or with oil between them, and all painted surfaces, were completely preserved. The detailed condition of the various parts, and the measures taken to restore them, were as follows:

Cylinders. These had partially filled through the hot-well, and from the drain cocks being open. The lower part of the intermediate cylinder was softened for 12 in. up, and was re-bored

in. larger in diameter, and the piston altered to suit. The piston-valves and liners in the high-pressure and intermediate cylinders were softened at their lower ends; the liners were rebored, and the valves fitted with new rings. The lower edges of the low-pressure slide-valve and face were also softened; the valve was planed, and the lower bar of the face chipped off and replaced by a brass strip pinned on. In all other respects they were sound and good.

Piston rods and Connecting-rods were turned all over, reduced 3-16ths in. in diameter, and the former fitted with new neck and gland bushes.

Guides had 1-8th in. planed off them before a hard surface was reached; and the guide shoes were lined up to suit.

Valve Gear is of the Hackworth type. The valve-spindles and various rods were turned all over, to remove the deep pitting; the angle blocks had their planed surfaces reduced 1-8th in., and the various parts lined up to suit.

Shafting. The crank webs were deeply corroded; but as there was ample strength, they were filled with "hard stopping" and painted. The shaft journals and crank pins were pitted longitudinally in the exposed spaces between the white metal strips, and were also pitted transversely at the clearance spaces next the crank webs; these were cleaned out, filed up, and the bearings adjusted. The thrust shaft was inuch corroded at the exposed parts of the collars and journal; it was turned all over, and the horse-shoes and bearing were re-filled with white metal. The intermediate length of tunnel shafting was much corroded at the exposed part of the journal; and as it was also reduced by wear, a new journal was turned further forward, and the bearing shifted to suit. The propeller and propeller-shaft were found in good order.

Auxiliaries.-The centrifugal pumping engine was considerably wasted in the rods, guide, &c.; and was treated like the main engines. The duplex pumping engine and donkey-boiler pump were so seriously corroded as to be useless, and they were replaced by new. The brass steam-valve and one pet-cock of the duplex pumping engine were curiously wasted into holes; and the checkvalve and seat on the main boiler had the appearance of some substance, probably zinc, having been sucked out of them.

A

Pipes.- From the appearance of the donkey copper feed-pipe it was feared that all the copper pipes were seriously affected. similar bend in the main feed-pipe was therefore sawn through, but was found to have suffered no deterioration. All the pressure pipes, however, were taken down, tested, and annealed; no defects were detected, and they were all replaced. But in putting together the various steam and vacuum gauges the small connecting pipes were found in several places to be curiously wasted below the coupling nut.

Small Details. It is unnecessary to enumerate the bolts, nuts, cock handles, spanners, and such small details, which were wasted into mere shadows of their former selves, and had to be renewed.

Boilers. The safety-valves of the main boiler having been eased when the vessel was beached, the boiler had filled with water; and the condition of both boilers looked serious. The front end plate of the main boiler was considerably wasted; the furnaces, which are of the spiral corrugated type, had corrosive scores running in the direction of the corrugations; and the tubes were covered with a deposit of what appeared to be pure metallic copper. In the end, however, after careful drilling and gauging, it was found that an unexhausted margin remained in all except the tubes. These were all found to be seriously corroded in both boilers, and every tube was therefore cut out and renewed; after which the boilers were satisfactorily tested.

Steam Trial.-Although the utmost vigilance and care had been exercised in examining as far as possible every point and detail, latent defects might have existed; and it was not with complete confidence that steam was again raised and the machinery tried. Neither then, however, nor in the months of continuous service which have since elapsed, has the slightest defect been perceived; and the machinery is now, thanks to its thorough

overhaul, working with the efficiency and economy which it possessed when new.

Conclusions.-The lessons to be learnt from this experience are probably obvious enough. Some of them are for the shipowner rather than the engineer, and therefore need hardly be referred to here; but it may be well to emphasise two of the others.

First, the advantage of having, in marine engines and boilers, a small margin over the actual requirements for strength. In the various rods, shafts, and similar parts, such a diameter as would allow them to be skimmed up; in the cylinders, valves, &c., such thickness as would allow them to be bored or planed afresh; and in the furnaces, combustion chambers, and stays, a slight excess of thickness over that required by the rules.

Second, the advantage of good paint. Many engineers prefer polish to paint; but in this instance the latter truly cost little, and was worth much.

Barrozo.-On August 26th Sir W. G. Armstrong & Co., Limited, launched from the Elswick shipyard, Newcastle-onTyne, the Barrozo, a cruiser built to the order of the Brazilian Government. She is built of steel, her under-water portions being sheathed wood and coppered. Her principal dimensions are:-Length, 330 ft.; breadth, 43 ft. 9 in.; draught, 16 ft. 10 in.; and displacement, 3,450 tons. The Barrozo will be provided with guns of Elswick pattern, the armament comprising six 6-in. quick-firers of 50 calibres in length, four 4.7-in. quickfirers of 50 calibres, ten six-pounder and four 1-pounder Nordenfelts, four Maxim guns, and two field guns. She will also have three torpedo tubes. The six 6-in. guns are arranged to fire three ahead and three astern. She is protected throughout the whole of her length by a curved steel armour deck. This deck completely covers all the machinery, magazines, and steering gear, and additional protection is afforded by the reserve coal bunkers, which are carried along the vessel's side to a height of about 6 ft. above the water line. With full bunkers the vessel will be able to traverse a distance of about 8,000 knots at a moderate speed. The vessel is fitted with twin screws and machinery of 7,500 I.H.P. She is expected to attain a speed of 20 knots.

The approximate traffic return on the Manchester Ship Canal for July states that the total receipts were £16,602, against £12,504.

Magnolia Metal.—The impression sought to be made that this metal is no longer being supplied to the trade, or to those desirous of using it, is quite contrary to fact. We have received a removal notice from the Magnolia Anti-Friction Metal Co., of Great Britain, Limited, that they are now carrying on the business of supplying this metal, as sole licencees for the sale in Great Britain, her colonies and dependencies, and in Continental Europe, under the original patents at 49, Queen Victoria Street, London, E.C. In the meantime the records of this metal, as an anti-friction metal, have not been standing still. We see that so late as August 20th, 1896, this company has obtained a splendid testimonial from Messrs. J. & H. McLaren, that when testing their 200 H.P. electric lighting engines for the South Shields Corporation upon the brake in their works for brake H.P., the main bearings and connecting rods being fitted with Magnolia metal bearings, they obtained the remarkable efficiency of 94.2 per cent., which we should imagine is quite a "record" efficiency-most creditable both ty the workmanship of Messrs. McLaren's engines and to the antifriction character of the bearings.

The Strike at Chiswick.-A further meeting of the boilermakers involved in the dispute which has occurred at Thornycroft's Torpedo-boat Building Works was held at Chiswick on August 26th, to consider the proposal of the firm that the remaining points should be referred to Sir Benjamin Baker for arbitration. The proceedings were private, but it was afterwards stated by the officials of the union that their members had decided to accept the proposal, and that all the boilermakers who were out on strike, together with the labourers who had been thrown out of employment in consequence of the dispute, would resume work.

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