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What About the Turbine?*

By Robert Cromie

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HE Hon. Charles Algernon Parsons, M.A., D.Sc., F.R.S., etc., proprietor of the electrical and engineering works of C. A. Parsons & Co., at Heaton, Newcastleon-Tyne, and Managing Director of the Parsons Marine Steam Turbine Co., Ltd., is the fourth son of the third Earl of Rosse, the celebrated astronomer whose telescope at Parsonstown was for a long time the largest in the world. Mr. Parsons is thus the distinguished son of a distinguished father; and as inventor, or perfecter, of the marine steam turbine, he is now one of the most prominent figures in modern engineering. Mr. Parsons was educated by private tuition and at St. John's College, Cambridge. The biographical brevity, "Scholar 1873; 11th Wrangler 1876," attests the distinction he won.

But all other honors and activities must give place to his position as the sponsor of the marine steam turbine, albeit that innovation has an ostensible history of less than a decade. By "ostensible" I mean that it is only nine years since the Turbinia made that marvelous dash of forty miles an hour round the fleet at Spithead, on the occasion of the Diamond Jubilee of Queen Victoria. That epochmarking incident introduced a new feature into practical mechanics, although we may be certain that the little vessel, in spite of her meteor-like appearance and performance, was not the result of a lucky guess, but rather the outcome of many years of patient experiment and searching investigation. From that first, I might say sensational, public performance of the Turbinia, the progress of the engine has been always steady; latterly it has entered upon a triumphal march.

Extracted from an article in the "World's Work and Play."

The Turbinia was only 100 feet long; the Lusitania, the mammoth Cunarder, is nearly 800 feet long. The Turbinia was engined up to 2,300 horse-power; the Lusitania will be engined up to nearly 70,000 horse-power. That is an extraordinary advance in a decade. There is nothing like it in the history of mechanics.

It must be remembered that the reciprocating or piston engine had been the subject of a century's experiments and improvements when the turbine challenged it on even terms. I am aware that the whole of the turbine case is not admitted by all engineers; indeed I am acquainted with some, whose opinion I value, who stoutly dispute the turbine's superiority. But I think there are few who would deny Mr. Rankin Kennedy's carefully weighed declaration, that, whatever may be in store for the turbine, the piston engine has now reached finality in that form. In order to introduce a short sketch of the present position and probable future of the steam turbine, I shall briefly indicate its history in the last decade.

The Turbinia having demonstrated the practicality of the invention, she was succeeded by the gunboats l'iper and Cobra: and these having met with mishaps, timid soothsayers prophesied evil for the turbine. In spite of their jeremiads, the engine was installed on the Clyde steamer King Edward, built by Messrs. Denny Bros., of Dumbarton. That was the first start of the steam turbine for use in commercial steamers. In the year which followed the advent of the King Edward, the Queen Alexandra was added to the turbine list by the same firm, and several improvements were introduced which added to the speed of the vessel without increasing proportionately the power of her engines or her coal consumption. Then more gunboats were turbine-engined; private yachts followed the lead;

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the Royal Navy joined in with larger ships; and while the first turbine cruiser, the Amethyst, was only 9,800 horsepower, the turbine Dreadnought, launched a few months ago, will be the most powerful warship afloat.

Meantime the commercial progress of the turbine was not less of the leaping and bounding character. The AngloFrench cross-channel service followed the example of the Clyde, and in turn was followed by the Irish and English Channel boats. Long-distance steamers to Australia and New Zealand took a hand in this wonderful game (the Loongana proved very satisfactory), and the attack on the Atlantic was led by the Allan Liners Victorian and Virginian. In the last phase, it is true, fortune proved unkind for a time, and the turbine's future seemed to have passed under a cloud. But the cloud since then has cleared away, and the sun of destiny shines as strongly as ever on the new engine. With the launch of the Lusitania, most progressive marine architects and engineers have agreed that at least for fast passenger steamers the day of the piston engine is passing, and will soon have passed, like so many of man's inventions, into the void of things that have been.

This matter of fast steamers is important, for it is a limitation of the turbine in its present development that it is not a profitable engine for a slow ship.

In his presidential address to the Institute of Marine Engineers at Stratford in January, 1905, Mr. Parsons put the matter of high revolutions in the piston and turbine engine very succinctly :

"The high revolutions which we dread in the reciprocating engine are a boon with the turbine, where bearings and thrust bearings are automatically lubricated, and the higher revolutions mean smaller screw-shafts and propellers, and less weight on the tunnel blocks."

Another feature is the deeper immersion of the propellers, owing to which even turbine yachts can cross the Atlantic in heavy weather without any perceptible racing of the engines.

As regards the turbine's future, Mr. Parsons has no fears. In vessels of 16 knots sea-speed and upwards, and over 5,000 indicated horse-power, he is confident that it will soon entirely supersede

the reciprocating engine; and this limit will possibly include before long vessels. down to 13 knots of 20,000 tons and upwards. Even slower ships may be brought into line later; and, although only in its early infancy, the turbine would now be suitable for one-fifth the total steam tonnage of the world. This is a striking object-lesson on the rapidity of the march of modern mechanics.

It is interesting to learn that Mr. Parsons thinks it probable a combination of the reciprocating and turbine engine will be found the best machinery for vessels of the "tramp" class in the immediate future. In a slow vessel it is manifest the revolutions must be low, because a certain disc area of propeller and a certain number of square feet of blade area are necessary in order to avoid too great a slip ratio, and consequent loss of propeller efficiency. The highest revolutions possible must be accepted; but these in, say, a 10-knot ship, are but a low figure. From technical reasons, the turbine is not highly efficient under these conditions. But the turbine can deal economically with very low-pressure steam, and in the ordinary "tramp" the steam, although usefully expanded down to about 7 lbs.' pressure absolute, is then released into the condenser, and the remaining energy, down to about 11⁄2 lbs., is almost entirely lost. The turbine picks up 70 per cent of this waste product, and turns it on to help in the driving of the ship. Mr. Parsons is very clear and also very confident on this really wide field for turbine employment:

"The additional power gained by the use of this low-pressure turbine has been calculated to be between 15 per cent and 20 per cent of the whole now realized-a gain of the same order as was obtained in the advance from the compound to the triple engine. This is the main feature of the case; minor points, of course, there are such as improvements of the condenser (as a good vacuum is very essential to all turbines for the best results) and also feedheaters fed from the exhaust of auxiliaries, or low-pressure steam drawn from the main engines for heating the colder feed due to the higher vacuum; and there are also other minor points; but I am sure that some arrangement, such as I have endeavored to indicate, will be largely used for the 'tramp' engines of the near future."

There is still another new field for the marine steam turbine, and in it a beginning has now been made-namely, the

propulsion of torpedoes. In some respects the United States Bliss-Leavitt turbine torpedo is much like the Whitehead, but it far surpasses its prototype in speed, range, and accuracy. While the Whitehead goes 1,200 yards at 28 knots, and up to 2,000 yards at 22 knots, the Bliss-Leavitt goes 36 knots up to 1,200 yards, and 28 knots up to 3,500 yards. The new torpedo is being made in two sizes. One is 18-inch, which can be fired from the 18-inch tubes on existing battleships and torpedo-boats; the other will be much more powerful, the size being 21-inch. The engine employed for the propulsion of this miniature warship is the Curtis turbine, compound type, with two propellers adapted to run in opposite directions. The turbine runs at 10,000 revolutions a minute, geared down to 900 revolutions for the propellers, and at this speed the new torpedo developed 40 knots, although the contract was only for 36. A turbo-gyroscope is driven at a speed of 18,000 revolutions per minute, and by this ingenious invention the torpedo is prevented from deflecting deflecting from its

course.

I believe most engineers admit that an "internal-combustion" turbine would be an ideal machine; and although there are difficulties in the construction of a satisfactory gas turbine, scientific invention has not yet said its last word on the subject. Heinrich Zoelly, of Zurich, has patented a gas turbine which is said to be a good machine, but I am not acquainted with its design or results. Last year, Emil Capitaine installed a producer-gas. turbine engine on a little vessel 60 feet long; and during a ten hours' run, at 13 knots, only 467 lbs. of anthracite were consumed, at a cost of about four shillings. Theoretically the gas turbine offers as good a thermo-dynamic efficiency as the piston engine; but the main difficulties in its progress are the apparent necessity of working at such high initial temperatures that no known constructional material could long withstand their action; the high rotative speed demanded in order to realize good efficiency; and the difficulty of compressing the elements of combustion to the high pressures of the turbine, and burning them under this pressure. It is believed that the wet gas turbine will remove the first two of these

difficulties, and that it is the third which will prove the most serious. When it has been overcome, the engine will be a splendid drive for the automobile.

Before concluding, I should like to mention only a few instances of the present position of the turbine ashore. Neuchâtel has now a combined system of steam turbine and hydraulic power for delivering current. At the Rhenanian Wesphalian Electricity Works at Essen, two units are being (or have been) installed of 10,000 horse-power each. These are the largest stationary machines ever built in Europe; and a Westphalian mining company intends putting in another 10,000 horse-power engine, also of the Boveri-Parsons type. Boveri-Parsons type. The French-Belgian syndicate control a number of electric plants at St. Denis (30,000 horsepower), Sclessin near Liége (15,000 horse-power), and Charleroi (3,500 horsepower), all turbine-driven. New plants are being erected at Brussels, Ostend, Cairo, etc., bringing the total horsepower up to 65,000, all installed within three years by the same company. America, progress is also reported.

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Mr. James Denny tells a good story of the trial of the Viper which throws a light on Mr. Parsons' character. preliminary trial trip was made early in the day, and the bearing of the engineers was ominous. They differed with Mr. Parsons as to the trial trip rate of wages, and as the latter knew his own mind the engineers walked off the ship. Every one thought the day's proceedings must end there and then; but Mr. Parsons thought otherwise. He turned on his apprentices. to do journeymen's work, picked up some men off the quay, borrowed some more from Messrs. Hawthorn, Leslie & Co., who had the contract for the hull and boilers, and made all into a scratch crew for the trial trip. Under these extraordinary circumstances, the l'iper ran her trial, and on that day did the unparalleled speed of 37 knots. When Mr. Parsons emerged from the engine-room, dirty and warm, all crowded round him to congratulate him, but he took the whole thing as a matter of course. It is a modern instance of how dangers retreat when boldly they're confronted. But it is not given to every one to confront mechanical difficulties so successfully.

Colossal Asparagus Plantation

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By J. Mayne Baltimore

SPARAGUS, which is deemed a great luxury in a vegetable way, is grown successfully in many parts of the world-particularly in Germany and the United States. However, in probably no portion of the globe is this delicious vegetable cultivated on a more gigantic scale than in California.

The Golden State may truthfully boast of possessing the largest asparagus farm in the world. It is located on Bouldin island in San Joaquin county. This island is formed by the junction of the San Joaquin and Mokolumne rivers and a connecting tidal stream. In superficial area, the island contains about 7,000 acres. Asparagus is here grown almost exclusively, about 3,000 acres being in cultivation. Besides Bouldin island, two other smaller islands are also partly in asparagus cultivation-Tyler and Andrus islands. Venice island, also, will soon be used as an asparagus plantation.

To care properly for the great crops on Bouldin, calls for a mammoth industry. The annual output exceeds 4,000 tons of asparagus. The season is very brief, lasting only from March 15 to June 15. When in the height of the "harvest," about 1,500 persons are employed. This force includes the work of cultivating and canning the enormous crop.

Most of the immense output is canned and shipped to the various markets of the world, though great quantities are disposed of in the local markets. Several large canning establishments are kept very busy during the brief season

turning out daily on an average 650 cases, or, about 20 tons of canned goods. There are also several smaller canneries employed to assist in handling the gigantic crops.

The total value of one season's crop reaches over half a million dollarsabout $600,000. More than 650 cars are shipped away during one season. The

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PART OF GREAT ASPARAGUS PLANTATION ON BOULDIN ISLAND, CALIFORNIA.

Showing plants in cultivation.

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