RENNIE'S FLOATING DOCKS.

Otago Daily Times, Issue 113, 27 March 1862, Page 4

RENNIE'S FLOATING DOCKS.

Now that Spain is endeavouring to regain, her position amongst the chief nations in Europe, and is reconstructing'and increasing her navy, it is found that the'docks which, were hitherto of ample .capacity for vessels formerly built are totally inadequate for the accommodation of the enormous line-of-battle ships and iron-cased frigates of which the navies of Europe are now composed. It has therefore been determined, 'without delay, to provide dry-dock conveniences of sufficient dimensions for the largest vessels in con-' templatiou, and a floating dock having been considered most advisable to be adopted in the arsenals of Cartliegena and Ferrol, the plans of Messrs. George ' llennie and Sons have been decided on as most suitable for the purpose, and the firm has been instructed to provide the two above-named arsenals with floating docks, to be constructed according to the principle-and patent taken out by them. These peculiar docks are' being completed at the -works of the firm, plolland-street, Blackfriars-road, previously to their being shipped for their destination. We give a brief description of them. They consist of rectangular pontoons, made of boiler -plates, divided into watertight compartments- by one middle division •or bulkhead, the whole length of the dock and nine transver.se divisions or bulkheads forming twenty watertight and distinct compartments. From each of these compartments there is a pipe in communication- with what is termed the "pump chamber," by which means any of" the compartments can either be filled or emptied with the greatest facility. ' ' ' :; ■; '.':■■ The following are the dimensions [of the pontoons prepared by Messrs. Kennie and Sons for the Government of Spain—viz., the base cf the . '. ■ . Cartha^ena Dock. Ferrol Dock. Length "320 ft. Oin. Length . 350 ft. 4in. Breadth 105 ft. Oin. Breadth. 105 ft. Oin. Depth. lift. Gin. Depth . 12ft. 6in. Such is the great power brought to bear in the con- . struction of these docks that they are capable of raising ships of from 6000 to 70U0 tons burden. On the longer sides of the base are constructed hollow walls, the outsides of which are perpendicular, and the inside sloping, with strong steps, such as are made in ordinary graving or dry docks; but the ends of the area are open, having neither walls nor gates. On the top or deck of each of the sides, at the middle, are placed the engines and boilers, together with the gear for working the sluices used for.filling or empty- ■ ing- the .different compartments during the process ordocking or uudocking ships. Tiie pumps are placed in a chamber near the bottom of the dock, immediately under the engines/ This chamber, as well as a similar one containing the regulating sluices, are made perfectly.watertight, and are in-communieation wkh the deck, in order that they may be examined or repaired when required. • • . The method of docking a ye: s ;1, according to Messrs. Rennie's system,.is somewhat similar to that of the ordinary process. After the dock is sunk to the required depth, so as to float- in the ship, th? vessel is worked in and placed over the keel-blocks, and shored up as the water leaves her sides; but this .water — namely, that occupying the space between the sides of the vessel and tlie dock—instead of either being pumped out or allowed to run out as the tide falls, is displaced in consequence of the whole dock aud vessel being entirely raised out of the water. This is done by pumping, or. forcing out the water from the chambers or departments forming the rectangular base— care being, taken to keep the dock in about a horizontal position by regulating the water in the different compartments by the sluices worked from the uppermost deck. This process is continued until the vessel is sufficiently above the level of the water to permit her being repaired. The repairs being completed, the dock is again sunk, and the vessel floated out. :. The repairs of ships in dock often take several months to complete them, and thus preventing the dock from being used for those constant examinations; such as clearing and painting, which are required for the bottom of vessels, it was proposed by Messrs Kennie to make a shallow basin of about 15 feet in depth, in order that the dock might be floated in with the vessel, which was to be placed end on the quay-wall, and hauled on horizontal erround by means of hydraulic power.. The dock would thus be available for other vessels. This plan is now being carried into execution, and will be cabable of allowing several vessels to be repaired at "the same time.— lllustrated London News, Jan. 18. •

The following statement relative to the disasters of the ship " Atieth Rahamon," in a hurricane, off the Mauritius, will be read with interest: —" On Saturday, January 4, we had all sail set, with steady breezes from the S.W. At about three p.m., Captain Jones noticed the barometer going down rather fast, on which we shortened sail to double-reefed topsails, foresail, and foretopmast staysail: got royal yards on deck. The wind increased as tie sun went down. At seven, p.m., under foresail, and at eight, p.m., it blew a gale of wind, At nine took in mizen topsail, sud a little after that, in trying to close reef fore-top-sail, the sail split. We then tried to close reef maintopsail, but the Lascars were afraid to go on the yard, so it'had to stop as it was till daylight. Had we at this time been able to get the ship with her head to the northward we"should have avoided the heaviest of what we got afterwards, but the ship would. neither wear nor stay. At daylight occurred one of those disasters so common at sea. The jib being partly adrift, eight men were sent in a bit of a lull between the squalls to make it fast, when the ship gave two or three tremendous plunges, and three men were washed away. The ship having no way, but drifting

bodily to leeward, they drifted away from her to windward. It. was impossible; to lower a boat iiibuch a sea. and it was haart-b.-eaking to Si"j axil hj.it theio poor fellows and not hi able to render them the least 'assistance. It hud the effect of dNhcaicmiin^ the rest of the crew to such a degree that even in daylight ifc required a, strong excrliu.) of authority to get them up to close reef the Eiaintopsail. 'Die sea hurl been gradually getting heavier ever since the^ breeze cama on, and at noon on the Stk the ship' was plunging herself right under -water, and burying herself sometimes completely from the after part of tlie fore-rigging forward. The. ship now commenced leaking, so much so that she re-quired, continual pumping;; tlie gale increasing nil tiny, until at midnight it blew a hurrienne, gradually veering round from S.W. to W.N.W. The scene at this time was fearfully grand. This continued till .about 4 r > minutes past 4 a.m., Jan. 6, when the mainmast went about thirty-six feet above the deck, carryit.g with it the inizeii topmast by the cap, and cross-jack yard, which fell on the poop, smashing starboard quarter boat, skylight, and barometer, breaking: in (wo pieces; the inizen topmast fell also, partly on the poop deck and partly overboard, smashing port, quarter; the main yard fell on the long- boat, smashing it and another "small boat stowed them all to pieces, breaking down boat's skid on quarter-deck, staving in the lifeboat in several places, breaking down front of the poop, smashing the sideboard with all the cabin crockery—almost everything in the mate's cabin. The maintop fell on the port gangway, breaking down three stanchions and greater part of top-gallant bulwarks. This part of the wn'ck got under the ship's bottom, and coming up on the other side caused great anxiety, lest it should make a hole in the ship's bottom, until it was finally cut away. At half-past five the foremast went about ten feet above the deck, carrying with it the jib-boom, and all that was left forward .was the fore^topsail yard, which w;i« lodged on the forecastle, and p.irt of the topmast with topmast c ros-troes, which went through four planks of the forecastle deck. The Lascars beingparalyzed with fear, were employed at the pumps, whicli at one time were so jammed wilh the mainyard that they could not be worked. At 8 a.m., we' found that the ship was making a great deiil of water, and settling down fast, in fact there appeared cvei-y probability of the ship foundering with us. Captain Jones .on this determined to throw cargo overboard, to try find lighten her; turned to accordingly, with passengers and as many men.as cpnld.be spnred from the pumps, and commenced getting cargo up through the cabin and throwing it overboard. Throughput: this day and Tuesday the 7th. the hurricane continued unabated; pumping and throwing cargo overboard;all the time, the sea malting a complete breach right over the ship, smashing and breaking everything moveable about the decks — Lascars, chests, and all the hencoops with'the poultry. No one on board expected the ship would live the hurricane out, leaking in the way she did, the quarter galleries washed away, and having torn out some plank ends of the stern. On Wednesday, January 8, the weather began to moderate, and having discharged nearly all 'tween deck cargo, the ship got, lighter and more buoyant on the water. Tow ards evening of that day it-was comparatively fine. On Saturday January 11, we got sail on her, and shaped a course for Mauritius, where we arrived on the 24th Jan. Lat. lGdeg. 25min. S., GBdeg. 35min. E., when dismasted.

A French Ship op/War.—The French war ship rinfernaL" was totally destroyed by fire in the harbour of Valparaiso on October 1, where she had arrived only two days before. The flames burst forth from between decks in the middle of 'the day, and got such a head that the- fire engines could do no good. Upwards of a hundred cannon shot were fired at the vessel in the hope of sinking her, but after six hours' of useless efforts of all sorts to extinguish the conflagration, it was decided to set lire to the powder magazine, and then the Infernal was blown to attorns in a moment. The explosion shattered a prreat many windows in the town. The loss is estimated at upwards of two millions and a half of francs (L 100.000).

We learri from the Sydney papers that all the Men of War belonging to the Australian station, are con-' centrated in Sydney harbour, Tiaiting" for further intelligence from Europe. This -will account for the sudden'removal of the Pelorus from New Zealand, which recently gave rise to much conjecture. The'Marco Poio.—This vessel, notwithstanding her having on her last passage home from this, struck against an iceberg, and thereby receiving such severe damage that it was a matter of speculation if she would ever come out here again, arrived in Hobson's Bay during Sunday night, under the command of Capt. Arnold (late of James Booth). She left Liverpool on the evening of the 12th of December, and was detained by head gales for five days in the channel, and again for ten days on this coast, owing to light easterly winds. During the time of the Marco Polo laying at Liverpool, she underwent a thorough overhaul and refit, and is now almost a new ship again, and, if we may judge from the expressions of the passengers, as great a favourite as ever.— Weekly Affi; March 14. .-. ; . ,-....-■' ■.'.-:'- T

Cheating tub '' Ciieei'Ek."—;\Ve (Dundee Advertiser) are told of a, trick having been played off on some 'unlicensed dealer in town, which, while it possesses the merit of cleverness, is almost commendable, since it punishes tlisse who openly, yet without legal punishment, break the law. Some of these dealers who have been laying in their stock for the New Year having had occasion to '' tap several of their ■ newlybought gallons, found the stuff of very good quality,, and also found it very difficult to run oft". Un exainigation,,- it appeared that a small cup containing a few gills, had been ingeniously let into the mouth of the jar, and while this was filled with excellent spirits the lower,, part of the measure necessarily remained empty. d ...-....,