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article number 719
article date 05-24-2018
copyright 2018 by Author else SaltOfAmerica
Our Technology, 1922 - Part 5b: Transport - By Sea
by Various Popular Science Magazine Writers
   

From issues of Popular Science Monthly, 1922.

* * *

Motor-Ship Brings Us New Prosperity at Sea

Experts Claim Use of Diesel Engines Will Convert America’s Idle Freighters into Profit-Payers

By Charles Frederick Carter

EVERY reader’s pocketbook is skimpier than it ought to be, because of the huge losses incurred monthly by the Shipping Board in operating our emergency fleet. Every reader is bound to be interested, therefore, in this article telling how, in the opinion of many experts, we might convert our shipping losses into profits and, incidentally, realize our dream of making America the Merchant Queen of the Sea.—The Editor.

* * *

Is history, as wrought out in the life and works of the automobile, to repeat itself in the case of the motor-ship?

Will America soon lead the world in motor-ship building and operation? You may recall that the first few chapters of automobile history were far from flattering to American enterprise. For several years we just stood with mouths agape watching European manufacturers helping themselves to all the motor-car business in sight. But when we did come out of our trance, we swept the board.

Sea Supremacy at Stake

In the matter of the motor-ship we have surpassed the remarkable record for apathy and incapacity established at the beginning of the automobile industry.

Just a few weeks ago William Denman, former president of the Emergency Fleet Corporation, told a select committee of the House of Representatives that if Columbia wanted to hold her job as “Gem of the Ocean,” she would have to hump herself—building motor-ships by the gross. He predicted that unless the United States builds millions of tons of motor-ships, or converts steamships into motor-ships, we shall lose the battle for maritime supremacy and shall not have even a minor share of the world’s sea carriage.

   
Of the 1157 motor-ships in service during 1920, only 27 flew the American flag. The boat in the circle represents America’s motor-ship tonnage, as compared with the world’s tonnage represented by the big ship. In the first six months of 1921, 321 motor-ships were added and America’s share rose to 12%.

Again, Charles E. Lucke, professor of mechanical engineering at Columbia University, New York City, recently told a gathering of engineers and naval architects that it has “. . . taken some years to convince American shipping interests that the motor-ship is reliable; that America can build satisfactory engines without copying European models; and that American shipping interests have now reached the point of accepting the situation.” Professor Lucke also predicted that American motor-ship construction and operation will soon lead the world.

Shipping Board Has One Motor-Ship

The United States Shipping Board’s first and only motor-ship, the ’William Penn,’ completed after three years’ delay, was in New York not long ago, loading for a voyage to the Far East—a voyage to compare the Penn’s performance with that of the ’Eclipse,’ a stepsister steamship.

This tryout of motor vs. steam seems somewhat like a demonstration of the well-known fact that two plus two equals four; for before it began, thousands of steamships were tied up in the harbors of the world for lack of cargoes at living rates, whereas only one motor-ship was idle because of inability to get a cargo at a profit. Other motor-ships, constituting 1.7 per cent of the world’s tonnage, were busy as the proverbial nailer earning dividends for their owners, while the steamship still in service found it hard to come out even, to say nothing of earning dividends.

Still, if ’William Penn’ wants to humiliate its stepsister by a demonstration of superiority, there can be no valid objection. It is no more than an elaboration of the results of the trial trip when the ’William Penn’ made a mile an hour better speed than the ’Eclipse’ on 300 per cent less fuel consumption. Bearing in mind that the cost of fuel constitutes 43 per cent of the expense of operating a ship, it will be seen that this was no mean feat.

The prodigy which accomplished this is 455 feet long, 60 feet beam, 36 feet 8 inches deep, with a displacement, loaded, at 17,100 tons. Her two main Diesel engines, driving twin screws, have four cylinders with bores of 29 1/2 Inches and a stroke of 45 1/2 inches. At 115 revolutions a minute they develop 4500 horsepower. The bronze propellers are 13 feet 6 inches in diameter. Just to show how easily an American motor-ship can be handled, the William Penn’s engines were reversed from full speed ahead to full speed astern in thirty-two seconds.

There are three Diesel auxiliary engines, each of 100 horsepower. Only one of these is needed at sea, but in port two are in use for handling cargo and other little chores. The engine-room crew consists of fourteen men. All the machinery below decks was built in Copenhagen. The only American machinery is the ten 30-horsepower Westinghouse motors driving the cargo winches.

   
The American motor-ship “William Penn” is cut away above to show the port and starboard Diesel engines. Each of these engines will develop 2250 horsepower with less than half the fuel consumption of a steam-engine of equal capacity. The saving in fuel effected by Diesel engines in a 17,000-ton ship on a voyage of 15,000 miles is estimated at more than $30,000.

Comparisons Are Startling

The William Penn made 12.6 knots on its trial trip as compared with speeds of 7.7 to 10.8 knots by six stepsister steamships from the same shipyard. When it comes to earning capacity, the comparison is still more startling. It has been calculated that a motor-ship of the size of the William Penn can earn 66 per cent more on dead weight capacity, or 55 per cent more when carrying bulk cargo than a steamship of the same size.

Under conditions enabling the steamship to earn 11.2 per cent a year, a motor-ship of the same size would earn 17.4 per cent. Translated into dollars, this means that where a steamship would be able to earn $218.500 net in a year, a motor-ship would earn a net profit of $374,000.

At sea the steamship would burn 35.65 tons of oil a day: the motor-ship would need but 14.95 tons. In port the steamer would burn 5.5 tons of oil a day, while the motor-ship would do well with only .7 of a ton a day. For a voyage of 15,500 miles the cost of fuel for a steamship the size of the William Penn would be $45,900, while the Penn would need but $15,260 worth.

Extended to the 2536 steamships of 12,797,000 tons now burning oil under their boilers, the waste of the world’s rapidly diminishing supply of oil, as compared with the potential saving attainable by substituting motor-ships of equal tonnage, becomes appalling.

But the light is dawning at last on the shipping world. Lloyd’s ’Register’ recently reported that 194 motor-ships of 503,844 gross tons were building. Steamships no longer profitable, are being converted into motor-ships that promptly become revenue producers.

A typical case is the Swedish steamship ’Augusta,’ which failed to earn profits until she was refitted with a Diesel engine.

When it comes to new construction, the motor-ship is virtually the only kind of craft considered abroad. A large number of orders for steamships have been cancelled in the last few months, but no orders for motor-ships have been countermanded. The big builders are spending millions to increase the capacity of their shops to turn out Diesel engines.

   
Diesel engine of the type installed in motor-ships.

Some twenty large motor-ships were completed in European yards in 1920. Standardized craft of 15,000 tons capacity and 14 knots speed are normal and regular products, costing less a net ton cargo capacity than steamers. No fewer than twelve of the leading British ship-owners are having motor-ships ranging up to 14,000 tons built, while still larger vessels are under consideration. The same tendency is noted in Continental countries.

As for Germany, the fact that the existing fleet of steamers had to be surrendered to the Allies may be the determining factor of restoring the flag to the sea. Unencumbered by unprofitable steamships, the Germans are constructing Diesel-driven ships with great energy. One new yard with 19 ways is devoted exclusively to this type of construction, and the older yards are devoting particular attention to motor-ships.

And America? Well, It begins to look as if Professor Lucke would prove a good prophet. At last reports nineteen motor-ships of 143,850 tons dead weight capacity and 44,520-shaft horsepower were building in American yards.

The biggest single order was for four ore-carriers of 20,000 tons dead weight capacity and 11 1/2 knots speed. In addition, a dozen or more steamships were being converted into motor-ships.

No fewer than sixteen firms are building Diesel engines, while 120 others either have licenses for building Diesel engines of European design or are experimenting with original designs.

Why American Ships Lie Idle

The Pacific Coast is taking particular notice that while American steamers are lying idle there, foreign motor-ships are carrying wheat from Vancouver to Liverpool via the Panama Canal and making money at it.

The Pacific people are not unfamiliar with the motor-ship, for they built about eighty of them during the war. Most of them, however, were underpowered wooden auxiliary craft, unsuitable for ordinary commercial purposes. Several full-powered wooden motor-ships gave splendid service and are still in regular operation.

Altogether it would appear that in the future the motor-ship will rule the waves.

   
The ’Yngaren,’ is equipped with 3000 horsepower Diesel engines, making it the highest powered motor-ship now in service. Maritime experts figure that with such vessel, freight can be transported 60 percent cheaper than by steam-engine-driven ships.

Novel Hose-Hawser Carries Oil from Tanker to Ship at Sea

BY MEANS of a new flexible combination of towing hawser and oil-pipe, the difficult naval maneuver of taking on fuel oil at sea has been greatly simplified.

In transferring oil from a tanker to a battleship, it is out of the question for the two vessels to lie alongside and to pass a short pipe between their tanks. Even in a comparatively calm sea, the pitching of the boats would break the hose and might seriously damage the plates and bulwarks of both ships.

In transferring oil, the ship receiving the fuel is taken in tow by the tanker, so that a uniform distance is constantly maintained.

In the past the oil-hose usually has been tied to the towing hawser with short slings of rope. It has been difficult to pass this awkward double line between the ships, and the transfer of oil has been frequently interrupted by the kinking of the hose or by the slipping of the hose from the cable.

In the new invention, small steel cables are arranged in parallel about a flexible hose. Metal rings protect the hose from abrasion by the cables. The combined strength of the ropes is equal to that of the ordinary towing hawser, and the oil is thus pumped through the center of the towline.

As there is only one line to handle, it is said that the lines can be passed by three men in less than half an hour.

The oil-line is made in comparatively short sections, with each length coupled to the next by shackles fastened to the steel rings through which the oil-pipe passes, and by which it is supported.

The hose sections are connected with a universal joint. The line is made in sections for convenience in stowing, since it is too stiff to wind on a drum, and is laid along the vessel’s deck when not in use.

The combination of oil-hose and hawser weighs about 15 1/2 pounds a foot, and it is said that by its use oil can be transferred in any weather, while a speed of 16 knots an hour is maintained by the towing vessel.

   
THE NEW METHOD & THE OLD. Advantages of transferring fuel oil to naval vessels by means of a combination towing hawser and oil hose, as compared with the complicated method of tying the hose to the hawser, are graphically illustrated above.

How the short lengths of cable, surrounding the oil-pipe, are shackled to steel rings through which the pipe passes, is shown in the lower picture. Other rings at short intervals keep the cables clear of the oil-hose. Drawing by G. H. Davis. © Modern Publishing Company.
   
Flexibility of the new hose hawser eliminates the necessity of maintaining uniform distance between oil tanker and the vessel receiving fuel. Even when the line is slack, there is no danger of kinking or interruption of the flow of oil. Drawing by G. H. Davis. © Modern Publishing Company.

“Impossible” Midget Engine Has Giant Power

Every Ship a Profit Maker!

THE day when the seas will be spotted with busy American merchantmen, carrying vastly increased cargoes and operated at greatly reduced fuel costs, is nearer at hand because of the persistency of one American, Elmer A. Sperry.

Equipped with one of his compound Diesel engines, he firmly believes, a standard tank ship will be able to increase her annual earnings more than $340,000 and to equal the combined yearly earnings of two steamers of the same tonnage.

   
" . . . a standard tank ship will be able to increase her annual earnings more than $340,000."

How Revolutionary Diesel Invention Saves Cargo Space and Fuel

"It can’t be done,” the greatest experts said. But Elmer A. Sperry, engineer and inventor, did it. Read in this article how, after 30 years of experiment, he has perfected a compound Diesel engine that seems destined to push our idle ships out of quiet harbors into busy seas.

* * *

SHIPS that idly swing at anchor in our harbors—what are they waiting for?

Cheaper motive power and greater cargo space—two important factors that would raise the anchors of hundreds of American vessels, turning losses into profits—now seem assured with the perfection of the “impossible,” a compound Diesel engine.

Suppose some expert breeder should develop a superhorse—one that would pull harder than the average horse on the same amount of fodder, occupy one quarter of the stall space in the barn, eat cheaper food, and weigh only one tenth as many pounds. Wouldn’t that horse fatten any farmer’s pocketbook?

More Power in Less Space

Well, that’s just what Elmer A. Sperry, famous inventor and engineer, has done—not with horses for the farm, but with Diesel engines for ships at sea.

“Compound a Diesel engine? It’s mechanically impossible.” So say all the textbooks. So said a group of engineers in 1900, while reporting that “if the combustion engine could be successfully compounded a most important gain would be made in reducing its weight and size.”

Diesel himself tried to compound his engine, and failed completely.

But Sperry was one engineer who refused to admit that it “couldn’t be done.”

For more than 30 years he studied and experimented with compounded Diesels. His first patent was granted in 1892; and now he has succeeded at last in perfecting a compound Diesel-type engine that may revolutionize prime movers throughout the world, and that is almost certain to be adopted universally for vessels.

By solving two problems, each believed to be insuperable, Sperry has perfected an engine less than one tenth, and, in special instances, less than one twentieth the weight of an ordinary Diesel of the same power, occupying less than a quarter of the space.

   
A compound Diesel engine (inset) and a standard Diesel of the same horsepower are pictured to the same scale. The compound engine occupies less than one quarter of the space.

It will burn any kind of crude oil, while the Diesel requires a special, partially refined “Diesel” oil, which is far more expensive and cannot be obtained at all in out-of-the way seaports.

To state these facts in another way: by installing one of the compound engines, it is claimed that a standard tank steamer would increase her annual earnings about $340,000—or more than the cost of one of the new engines—by the saving effected through increased cargo space and reduction in fuel consumption.

A reduction in the weight of shaft horsepower from 450 pounds to less than 40 make it seem almost certain that compound engines will come into universal use at sea; but even more far-reaching uses may be expected.

Models now under construction will weigh less than five pounds a horsepower. This is close to the weight of airplane engines, and it may be that the compound Diesel soon can be used in aviation, assuring an increase of cruising radius and speed, as well as the total elimination of fire risk and the danger of accident from engine failures.

   
Five pounds per horsepower will be the remarkable rating of the tiny successor to the present-day Diesel engine.

The secret of Sperry’s success is the invention of a valve that will handle red-hot gases for months at a stretch without jamming. Its great efficiency is due largely to the fact that it eliminates some of the disadvantages of the Diesel engine.

In the ordinary Diesel cycle, air alone is drawn into the cylinder on the charging stroke. As the piston rises, this is compressed to over 400 pounds a square inch, which raises the temperature of the air so that it ignites the oil injected into the cylinder with a small amount of even more highly compressed air at the top of the stroke.

There is no spark, and the power is obtained without an explosion in the cylinder—the mixture burns very rapidly, and the cylinder pressures do not rise above those of the compressed and injected air.

   
Cargo space occupied by a reciprocating steam plant is indicated by the shaded area. Compare this with the small black space filled by a compound Diesel plant of the same power.

Defects that Sperry Remedied

To compress the air injected with the oil consumes about 10 per cent of the total power, and the three-stage compressor pumps often get out of order.

Again, the great weight of the Diesel is due to the fact that it is designed on the basis of an extremely small quantity of air or oxygen to be fired at each stroke. Less than 5 per cent of the cylinder volume—a mere crevice at the top—is actually occupied by an inflammable mixture.

Yet the whole cylinder must be strong enough to withstand the extreme pressure of firing, although during 95 per cent of the cycle the actual working pressures are comparatively low and should be utilized in a low-pressure cylinder.

But in the compound engine there are separate cylinders for the high and low pressure areas of the expanding gas. By introducing supercharging, or two-stage compression, large working volumes are secured in the cylinders, while the need of injection air and complicated three-stage compressor pumps is avoided.

As a result the clearance space, or working volume of gas, may be nearly five times that of the ordinary Diesel, and yet it is easy to bring this enlarged volume up to the requisite pressure and incandescent temperature at the instant of fuel injection.

The Source of Power

Bear in mind that there are two high-pressure cylinders—each four-cycle—delivering power on every other stroke, and one low-pressure cylinder—which is two-cycle—delivering power on every stroke.

As the low-pressure piston is impelled downward, it compresses a volume of air trapped on its under side. When this air is compressed to about 100 pounds a square inch, a bypass opens and it rushes into the first high-pressure cylinder, which is starting its charging or compression stroke.

By charging with compressed air, the amount of air inside the cylinder has been greatly increased, so that when the high-pressure piston rises, exactly as in the standard Diesel engine, and compresses the charge to 400 pounds a square inch, 25 per cent instead of 5 per cent of the cylinder volume is occupied by the incandescent air.

Compression starts from 100 pounds, instead of from zero.

With this large clearance volume there is no difficulty in igniting solid injections of heavy oils. Indeed, the oil is burned almost instantaneously and explodes practically like the charge of a gasoline engine.

Thus the gas pressure in the high-pressure cylinder of a compound engine does rise above that of the compressed charge, giving a gain in power at the very start of the stroke.

The entire high-pressure piston displacement causes the gas to lose only a fraction of its pressure. It comes to the low-pressure stage with sufficient volume and power to drive the low-pressure piston—which is 10 times the area of the high pressure—to the end of its stroke with gas pressures still above the atmosphere. The mechanical advantage gained by giving the gases this enlarged piston area to work upon is obvious.

Here, however, comes the great difficulty. The gases must be transferred from one cylinder to another while they are very hot. If they were allowed to rush into the low-pressure cylinder, they would quickly wear out the valve, and the drop in pressure would destroy all the gain of compounding.

The low-pressure exhaust valve is therefore closed slightly before the bottom of the stroke, and a small amount of gas is trapped in the upper part of the cylinder, which is again compressed on the upstroke so that when the transfer valve is opened, equal pressures exist on both sides.

   
This photograph of the compound engine, with cylinders removed to expose the pistons, was taken after about 1000 hours’ run on this remarkable engine.

Solving the Crucial Problem

Even so, the temperature is so high that the valves would become white hot if they were not constantly being cooled by the compressed air passing to the high-pressure cylinder.

Placing these two pipes one over the other, with a valve extending from one into the other, solves the crucial problem of compounding. The pressed air, owing to its density, has seven times the cooling power of ordinary air. The valve is heated on its under surface, and instantly cooled on a surface five times as great, so that it strikes a heat balance far below red heat.

The great efficiency of the compound is due to the fact that the pressures persist throughout the stroke. Though only slightly higher than those of ordinary Diesels, the pressures are in larger quantity, and useful work is obtained while the gases expand from about 500 pounds a square inch clear down to atmosphere.

Expansion Ratio Increased

In this way the expansion ratio, instead of being 3 or 4 to 1, as in the automobile engine, or about 2 to 1 in the Diesel, rises as high as 120 to 1 in the compound, and works through 315, instead of 120, degrees of crankshaft revolution. In other words, the power curve is 3 times as long.

More remarkable is the fact that the inventions which have produced this increased efficiency after years of experiment have, at the same time, greatly simplified the mechanism of the engine and entirely eliminated the troublesome three-stage air compressor.

   
Elmer A. Sperry and his compound engine.

Marine Engines Will Improve

By ALBERT D. LASKER, United States Shipping Board

* * *

THE past 20 years have shown almost as great a change in the characteristics of the world’s merchant fleets as
was to be found in the entire history of steam-shipping before 1900. The turbine, the oil-burning boilers, the geared turbine, and the internal combustion engine are products of the past 15 years alone.

The size and speed of the cargo ships have steadily increased, though, paradoxically, the extreme size and speed once popular for special passenger ships is now considered impossible because of construction costs.

Cargo handling gear has been greatly improved.

The use of electricity on board ship has become almost universal, while the tremendous strides in radio make possible communication at sea.

We seem to have reached the maximum efficiency of the steam generating plant as applied to marine propulsion, in the modern turbines. For the long hauls steam will be unable to compete with the internal combustion engine.

It would seem probable that some combination of steam engine and internal combustion engine will be evolved to give a decreased weight and size to the horsepower.

The popular type of passenger ship for the next few years will be of about 20,000 gross tons, making around 18 knots.

“Scrapped” Warships Become Busy Merchantmen

THE possibility of converting Uncle Sam’s six uncompleted battle cruisers, designed for tremendous power and high speed, into a fleet of the fastest passenger liners afloat, not only has been suggested by leading engineers as a solution of the "scrapping” program, but has been demonstrated as practicable by Germany’s success in
transforming obsolete battleships into merchantmen.

German ship builders have proved that the process of conversion, even when a battleship has been completed, is comparatively simple and inexpensive. The ship is placed in dry-dock, and the heavy armor belt stripped from the sides. Turrets, guns, and fighting tops are cut away with oxyacetylene torches, and lifted out of the ship by great cranes.

   
Converting a German battleship into a merchantman. The crane lifts a fire control mast. © K & H.

After the vessel has been completely stripped and lightened as far as possible, a vertical framework is bolted to the sides and covered with ordinary ship plating. This gives the converted vessel the usual appearance of the merchant ship, and the spaces thus made available are utilized for cargo.

The propelling machinery is, of course, left intact.

The six American battle cruisers remain incomplete, and hence the superstructure above the waterline, say engineers, may readily be replanned for merchant service.

Their enormous power plants, designed to give them speed of more than 33 knots as war vessels, would drive them at more than 25 knots as merchant ships, even with some of the boilers removed to reduce fuel consumption.

Their great stability, required for firing big guns, would make the ships steady in rough weather and permit the addition of extra decks, thus providing passenger accommodations large enough to warrant the expectation of operation at a profit.

The ingenuity with which the Germans have converted their obsolete submarines, that appeared at first to be absolute junk except for war uses, into a valuable commercial asset is demonstrated by the tanker ’Ostpreussen,’ which recently carried a cargo of oil from Texas to Hamburg. This ship was constructed by joining two submarine hulls in parallel, catamaran fashion.

A superstructure of the usual tanker form was built upon the curious under body to provide accommodation for the crew.

   
The merchant ship ’Ostpreussen,’ built of two submarine hulls, completing a voyage from Texas to Hamburg, with an oil cargo. © K & H.
   
The steamer Odin, former battle cruiser, passing through the Kiel Canal with a cargo of locomotives. © K & H.

Useful “Scrapping”

DELIBETE DESTRUCTION, under the naval disarmament agreement, of the great capital ships under construction for our navy is almost unthinkable. Engineers have estimated that the six newest type battle cruisers can be converted into 25-knot passenger liners, each capable of carrying 3500 passengers and 2500 tons of cargo and operating at a profit.

Forty-Two-Foot Crankshaft for Diesel Engine, Marvel of Accuracy

A FIFTY TON crankshaft 42 feet 7 inches long, with 12 throws, has just been machined in England for use in a marine engine of the Diesel type.

Though the shaft is installed in one piece, it is composed of four sets of cranks, each of three throws, connected with flanged coupling shafts. In spite of its size, the error in the total length was only 0.008 of an inch, and the largest error in the alignment of the journals was only 0.0012 inch—almost incredibly accurate.

   
50-ton crankshaft machined with accuracy.

Ship Sets Non-Stop Record

THE world’s record for a non-stop run by a motor ship is believed to be held by the ’Lobos,’ a 9000-ton freighter of the Pacific Steam Navigation Company, which steamed from Liverpool to Bahia Blanca—a distance of 6527 nautical miles, the journey occupying 25 days—without stopping her engines.

Echo Soundings Save Ships from Reefs

Depth of Water Is Now Measured by Timing Sound Vibrations Reflected from Ocean

BY GIVING a sea captain constant knowledge of the depth of water under his ship’s keel, even while the vessel is steaming at high speed toward land, an echo sounding device recently perfected by the United States Navy is expected to prevent liners from running aground in fogs.

The device is based upon the fact that sound waves in water behave as they do in air. A vibration in the water is reflected from the ocean bottom exactly as a sound wave is reflected from a brick wall.

By measuring the time required for a sound to travel from a sender at the keel of the ship to the ocean bottom and back again to microphones on both sides of the vessel, the captain can determine the depth to within a few feet of absolute accuracy.

Since sound travels nearly 5000 feet a second in water, the time-measuring apparatus must be exceedingly accurate, and in fact time intervals of 1/1000 of a second can be recorded.

The sound is produced by firing a cartridge under water. This cartridge is exploded by depressing an electric key on the navigating bridge. The same current starts the time recorder, which is stopped by a relay actuated by the reflected sound wave from the bottom.

   
By measuring the time elapsing between the explosion of a cartridge at the ship’s keel and the return of the echo from the ocean bottom to microphones at the sides of the vessel, the captain, knowing the approximate velocity of sound in water, can determine the depth.

Continuous Soundings Possible

If the bottom is rocky or uneven, the least depth will be registered; and this, of course, is what the navigator wants to know.

The new invention also makes possible a series of soundings only a few hundred feet apart. By the old method employing the hand lead or the sounding machine in which a heavy lead and many fathoms of wire must be reeled in after every cast, readings every quarter mile are about the limit.

By means of the intermittent sounds given by the new instrument, the knowledge that the water is becoming shallow will warn the navigator to change his course, or even to stop and anchor, long before the ship is in actual danger of touching bottom.

The device also will make it possible to measure spots in the oceans of the world which heretofore have remained unmeasured because of their great depths. One such spot is in the Gulf of Mexico, north of Yucatan.

   
The time-recording instrument.

Here’s the First Woman Marine Engineer

FOR the first time in the annals of the sea, a woman has become boss of the “black gang” on a seagoing ship. A license as a marine engineer has been granted to Mrs. Carlia S. Westcott, of Seattle, Wash., and she is now at work as chief engineer on a seagoing tug—no easy berth, as any sailor knows.

Mrs. Westcott declares that women are particularly well fitted for steam engineering, since the work is light, and the chief requirements are watchfulness and close attention to duty.

   
“Women make capable steam engineers," says Mrs. Westcott, and proves it.

Airbags Raise Sunken Ship from Mud

Six huge airbags or pontoons recently raised a yacht from the mud of a river after attempts to salvage the vessel by derrick had failed. The bags have rubber inner lining, walls of a double layer of heavy canvas, and are protected against shocks and abrasion by rope.

Below the surface all bags are filled simultaneously with air through a diver’s hose, and when inflated have sufficient buoyancy to pull a sunken ship from the grip of the mud and support it.

The bags were attached to slings passed under the hull through holes dug by directing a high pressure stream of water against the river bottom under the ship.

The enormous rubber balls were used also to raise from the ocean bottom the government ship ’Isis,’ wrecked off Florida.

   
The prow of the foundered yacht is seen between the two bags in the foreground. © Ewing Galloway.
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