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ing, running lines, repairing damages, and carrying on the ship's routine.

So much for young America.

The chief boatswain's mate was a tower of strength, as all chief boatswain's mates should be at such a time; but as youth goes in these days he is a veteran. He must be thirty years old, though he doesn't look it.

From these experiences, and from earlier work of this kind which has fallen to my lot, the following suggestions are offered to any who may need them.

(a) When going to the rescue of a stranded vessel, rig ship for towing and get up gear that will probably be needed.

(b) This gear includes heaving lines, light lines for running hawsers, heavy hawsers, fenders and shackles, shackling tools, small jiggers and heavy deck tackles.

(c) See that a good life boat's crew is ready.

(d) Provide a lead line marked in feet, and detail an officer or competent man to sound and make a sketch and record of soundings around the stranded vessel, and of the water in which the towing ships must work.

(e) Look up the state of the tide, the rise and fall, times of high and low water, prevailing set and drift, and the variation in the tide. This variation in the tidal rise may sometimes be of great importance.

(f) See that sheet anchor and chain, and kedges are free, and bitter ends of cables ready for slipping.

(g) Close water-tight compartments wherever practicable.

(h) Pick an officer for wrecking master, and a signalman to accompany him.

(i) Arrange simple signals. Give one copy of signals to wrecking master and post one copy on bridge. These signals should include, for night and day; 1. "moving," stop, 3. “haul,” 4. "all clear,” 5. “not clear,” 6. “ cut," 7. “ let

2.

go.”

Semaphore, by day, or blinker, at night may be used for all of these signals except 1. “Moving,” and 2. “Stop."

Stop.” Whistle signals, day or night, or flags by day and lights at night, should be arranged for reporting any movement of the stranded ship and for stopping the tow instantly.

(j) Put over, mark and tend a heavy drift lead on the stranded ship, and on each ship in position for towing. At night a quick

leadsman may inform the bridge that the ship has started ahead before report can come from aft that the line has parted.

If the towing ship has out a long scope of chain and stops her engines promptly after a tow line parts, or the stranded ship suddenly floats, then she will not gather headway enough to hurt anything

But she should not have out enough chain to extend back to her own propellers when the chain tends aft. A broken line may prevent the use of the engines.

(k) All should be in readiness to heave in the chain, or else to veer it and slip if necessary, to avoid a collision.

(1) As a rule the stranded vessel will have her anchors down, to lighten the bow, and perhaps for kedging. And there is little danger of the vessel colliding with the towing ship.

In the case of the Doheny, however, she had out only a small kedge astern. She picked up this kedge too quickly, fearing it would foul her propeller.

As a matter of fact, picking up this kedge too soon almost caused serious trouble. It allowed the Doheny's stern to drift across the wire towing hawser; but the Cincinnati's whale boat got under the Doheny's counter and cleared the wire before it fouled the screw. In doing the job over again I would make the Doheny let go a bower ‘anchor to check her sternboard when afloat.

Perhaps the most interesting minor detail in connection with the salvaging of the Pershing was as follows:

The Cincinnati shackled a wire hawser to her towing bridle and sent a hauling line from the end across to the Pershing.

In hauling the wire across it caught on a coral head on the bottom, and stuck. Steam winches and men could not move it, and the experiment was tried of underrunning the wire hawser by forcing the bow of a motor sailing launch along under the wire.

The coxswain of the motor sailer, a boy of nineteen, was ordered to stop the engine in order that he might clearly hear his instructions. With the engine stopped the boat was moved under the wire, and the crew began to haul it ahead. The bow of the boat wedged itself under the wire, and as the bow man walked the hawser aft the boat moved easily ahead, lifting the wire hawser from the bottom as it forged ahead.

Some component of the tidal current must have set the boat along the wire. Without starting the engine, with only the

pressure of a bight of the hawser behind it, the boat ferried itself quickly across from the Cincinnati to the Pershing in about two minutes, and the line was clear.

Captain L. H. Chandler, in the May number of the Naval INSTITUTE PROCEEDINGS, explains a towing trick learned from Chapman & Merrit, wreckers; the use of a spring on the tow-line to hold the towing vessel up against the set of wind or tide.

Within the past week I have seen a towing vessel forced to slip and run in order to save herself, when a spring from her bow to the tow-line would have held her safely in position.

Captain Chandler also quotes an experienced wrecker's axiom to the effect that beyond a certain point it is of little use to add to the strain on towing hawsers and kedges.

By very gradual increase in the strain on the towing gear a close approximation can be made to the maximum strain that it is advisable to put on the hawser. It may be advisable to break the weakest link in the gear in order to be sure. After knowing about what towing strain may be safely taken, it may be advisable to try towing at various angles with the keel of the stranded ship. The facilities for flooding, pumping, and shifting cargo should be carefully considered. They may solve the problem.

If a good diver is available it may be well to send him down to examine and report the underwater conditions.

The amateur wrecker undertaking salvage operations on an extended scale should prepare himself for many failures and disappointments; it is a job for Job, requiring infinite patience under adversity. On the other hand, it is a task where patience yields an almost sure reward.

In wrecking, the importance of the tidal rise and fall may vary greatly

In the salvage of a ship like the Doheny, with stern in deep water and ability to alter trim several feet quickly by shifting ballast, a small tidal rise may sometimes be neglected.

In salvaging the General Pershing the tide was the controlling factor. The best speed of discharging the cargo lightened the ship only about two inches a day.

The range of the tide was approximately twenty inches, which was equivalent to a lift of a thousand tons. It is well to remember that,

“There is a tide in the affairs of men,
Which, taken at the flood, leads on to fortune."

(COPYRIGHTED)
U. S. NAVAL INSTITUTE, ANNAPOLIS, MD.

RESILVERING SEXTANT MIRRORS By LIEUT. COMMANDER ROBERT T. YOUNG, U. S. Navy

At present when ships are making long sea voyages, frequently the navigator will find that his sextant mirrors are going bad and no spares available. He is also apt to find his sextant mirrors in such condition that although the sun can be handled, great difficulty is encountered with stars. If such is found, the mirrors can be very successfully resilvered with the facilities on board ship.

Frequently I have asked navigators and officers who have finished their navigator's cruise, if they ever resilvered their mirrors; invariably the answer was that they had tried it, but could not make it work.

The following system was used on a surveying expedition to the Sandwich Islands of which the writer was a member, and was found to be very successful; in fact, the system, we used entirely to keep the boating parties supplied with mirrors.

PREPARATORY (a) Get some tin-foil—that from the average package of cigarettes is entirely satisfactory.

(b) Obtain a small bottle of ether-alcohol from the doctorthis is used to thoroughly clean the glass.

(c) Get a few drops of mercury-should no other be available, a few drops from the artificial horizon will not be missed.

(d) Obtain some clear shellac—the gummy sediment which collects in the base of receptacle is better. If possible and near a navy yard, send the chief quartermaster over to the yard and borrow a small bottle of the substance used at the yard for that purpose.

OPERATION (a) Carefully unroll the wrapping of the cigarettes so as not to crumble the tin-foil. Cut out a piece about twice the size of that which will be required for the actual backing. Place this on a pad of paper, examine and see which side will be the better

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