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should be very carefully watched in giving her starboard helm, for if she will not clear by going ahead, full speed astern makes worse of the matter. These remarks apply when a vessel has more way on her than will pass the object, and too much to stop ber before reaching it.

No steamer can be steered to go straight astern, no matter what precautions are taken, as her propeller, in the end, if unaffected by tide or current, will eventually put her athwart, and if at sea turn her completely round, bearing in mind that with the right-handed propelier she will come round to starboard all the time, and the reverse with the left-handed propeller ; she will, if unaffected by the tide, pay little attention to the rudder at first, but of course use the rudder to help her round directly sho begins to get stern-way, or rather the rudder is of no nse to the ship till she gets steriaway upon her, for she will begin to cant long before the rudder becomes useful.

In coming astern and you want a steamer to come to starbo:ird with her bow, put ihe rudder hard to starboard, and rice rers with a left-handed propeller. If you wish her to cant to port withi a right-handed propeller, you cannot do so by going astern, as no matter which way you put the helm, if she have little way on her she will go to starboard, and the same thing reversed will occur with a left-handed propeller.

In turning short round at sea a steamer with a righthanded propeller turns quickest with her port helm ; thusSay you are going full speed ahead, put the helm hard a-port, and when she is on a full swing of port helm, stop the engines, and when she loses way bring the engines full speed astern and reverse the helm, viz., put it hard a-starboard, and she will come shorter and quicker round in this way than she will by going a-head at full speed with either helm.

Of course these observations mean if the ship is uninfluenced by tide, wind, or current, as either of these may cause a contrary effect to take place, therefore all circumstances must be taken into consideration. Wind or tide will cant steamers, especially light ships, against their propellers, and it must be observed that which ever way they first begin to cant they will continue to do so to the end ; that is, when going astern.

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BALLAST TANKS

The newest construction of ballast tanks has only one inlet for water, and this inlet is through a valve-box placed in the engine-room, which is under the control of the engineer, and all the ballast-tank valves lead into this box, which is well marked, viz.—fore hold, main hold, after hold, &c., consequently no water can pass into the tanks unless it comes through the valve-box in the engine-room, each tank having a separate pipe leading from it to the valve-box. These pipes are also connected by valves leading to the donkey engine, and are used to pump the water out of the tank.

There are also sounding pipes fitted to the tanks, which ought to be frequently used when the ship is full of cargo.

When filling the tanks great care should be taken that they are quite full, for if they are not completely filled it causes the ship to roll heavily, and puts great strain upon the tank top. This is easily known by keeping the sounding pipe cover off, for when the tank is nearly full the water will commence to fly several feet abuve the deck, but will gradually subside till the sounding-pipe is full to the level of the deck, when the tank will be quite full.

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SLUICES

The water-ballast tanks of steamers are seldom carried into the sides of the vessel, consequently between the outside of the tanks and the side of the vessel there remains a : space of about eighteen inches in width fore and aft of the tanks; this space is constructed as a water-way, and in which are the sluices. This construction is to afford means of getting the water to the engine-room in case the ship is damaged or holed above the tank tops.

The sluices are placed at the after end of the tank sides in the fore holds, and at the fore part in the after holds, and are situated at every water-tight bulk-head fore and aft on both sides of the vessel. The valves of these sluices are connected to a vertical rod that leads to the upper deck immediately above the sluice, and are covered by brass water-tight caps on the upper deck, which are marked so that you can see when they are open or shut, and that duty devolves upon the carpenter of the vessel. There ought to be a sounding pipe at every sluice, so that the holds can be sounded every four hours. The water-ways to the sluices should be frequently cleaned out, as they are the only means (excepting the hand pumps) of getting clear of any water in the holds when the ship is full of cargo.

The sluices are worked by a key, care always being taken that the brass cap on the upper deck is securely screwed on after altering them, as many cargoes have been damaged through inattention to this important point. RIGGING PURCHASES FOR LIFTING HEAVY

WEIGHTS. Heavy articles in steamers must first be lifted from the hold by a pair of shears on to the upper deck; these shears should stand athwart ships ; then to get them over the side another pair of shears is necessary, which should stand fore and aft; also two large spars are necessary, rigged out through the ports, securely lashed, and projecting about twenty feet outside her broadside. These spars to be fitted with heavy purchase blocks at their extreme ends, and are used to bowse whatever you are discharging out of the vessel clear of the side. After hearing up the article, whatever it is, by the athwart ship shcars, when it is level with the upper deck lash on the lower purchase block of the fore and aft sbears, and secure to this lashing the tackles connected to the bowsing-out spars before-named ; heave away upon the athwart ship shear purchase till it is some few feet above the rail, then hang that purchase off and belay it ; take the fore and aft shear purchase to the winches, and haul away upon the tackles fast to the bowsing-out spars ; this will take the article clear of the side ; at the same time keep slackening away upon the athwart ship shear purchase till the fore and aft shears have all the weight, then lower away at pleasure.

Use great care in securing the heels of the fore and aft shears, have them well cleated and secured with chains, so that they cannot lift upwards; many accidents occur with heavy weights by the fore and aft shear legs lifting, for if they lift an accident is inevitable. Locomotives have been discharged in this manner weighing nearly thirty tons each. The topping lifts for the fore and aft shears should be taken

one aft to the mainmast, the other to the foremast, and slackened away till the shear head plumbs the rail; too much care cannot be used in rigging these shears, as they are the chief cause of anxiety.

These remarks are mostly intended for long steamers whose masts are far apart, consequently none of their yards are of any use for discharging heavy weights ; also it is presumed that she is in an open roadstead, or in some position where no shore appliances can be brought to bear on her, and the seaman is left to his own l'esources.

If the seaman is afraid that the topping lifts of the fore and aft shears have tvo much drift, it will be advisable that two heavy preventive topping lifts be taken from the shear heads underncath her bottom and securely fastened on the upper deck on the other side ; this will seldom be necessary, but remember the sailor's old proverb-" better be sure than

It may also be observed that the fore and aft shear legs should be placed on the opposite side of the deck to that on which you are going to discharge the cargo, and the athwart ship shear legs placed at the after-part of the lateh, one on each side of the deck ; they all should be placed upon deck beams, which should be securely shored down below the upper deck; and good cleats should be put on the shear lashings at the shear heads to prevent them slipping.

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VESSELS IN DRY DOCK

When about to dock be careful the ship is on an eren keel and has no list either way, for if this is attended to she will take on the chocks very readily and easily ; be sure the holds are dry and no water in the engine-room bilges. It is generally the custom to knock a rivet out in each watertight compartment near the keel, so that the tanks may run dry, and can be washed out with fresh water before painting ; examine the fore and aft peaks well, as dirt and rust are mostly found stored up in these places; examine well the lower rudder gudgeons and the boss and keys of the propeller, also all the sea cocks and valves that are under water when afloat.

GETTING UNDER WEIGH

1. A steam ship under the spouts, or against a wharf, what

precautions would you adopt ?

Have fenders over the side to prevent chafe. Have

a bow and quarter rope to the shore to secure her. 2. In getting under weigh, what should be seen to before

the engines are started ?

Have a report from the engine room that everything is clear about the engines ; see that thers is nothing foul of the propeller; be very careful to haul in the slack of the quarter rope as it is eased off, for fear of the bight fouling the screw; and see that the wheel

chains and rudder are in perfect working order. 3. Describe any arrangement of sluices you know of ?

The water-ballast tank is made flat on its top till it approaches the sides, when it is made to curve down,

thus forming a gutter or sluice at each side. 4. What are they for ?

To allow any water that leaks in to find its way to

the engine-room bilges, where it can be pumped out. 5. How can it pass the bulk heads ?

There are sliding doors (called sluice-valves) worked from the deck, which, on being opened, allow the

water to pass through on its way to the pumps. 6. How do you clean out the limbers ?

By hand when possible. If the hand will not reach,

then by a soup and bouilli tin fastened to a rod. 7. What are the advantages of water-ballast tanks ?

A ship when being moved from one port to another in ballast saves the expense of buying and loading ordinary ballast, the expense of discharging it, and the loss through detention in both operations; because she opens her water-ballast cocks and allows the water to run in as she goes along; and as she is reaching her port she begins to discharge it through her donkey

ballast pump.

8. What disadvantage has it ?

When the ship is loaded and the tanks are empty, her cargo is too high, making her crank.

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