Part 9

As to the propellers, these approach closely to the usual form. It has, however, been found best to place two propellers of approximately the same pitch on each shaft at some considerable distance apart, so that the after one shall not be seriously affected by the wash of the one in front. The advantage of this arrangement is that a sufficient blade area is obtained to carry the thrust necessary to drive the vessel with a lesser diameter of propeller, and so permitting of a higher speed of revolution of the engines.

The problem was complicated by the question of cavitation, which, though previously anticipated, was first practically found to exist by Mr. Thornycroft and Mr. Barnaby in 1894, and by them it was experimentally determined that cavitation, or the hollowing out of the water into vacuous spaces and vortices by the blades of the propeller, commences to take place when the mean thrust pressure on the projected area of the blades exceeds eleven pounds and a quarter per square inch. This limit has since been corroborated during the trials of the Turbinia.

This phenomenon has also been further investigated in the case of model propellers working in an oval tank of water, and to permit of cavitation at more moderate speeds than would otherwise have been necessary, the following arrangement was adopted: The tank was closed, plate-glass windows being provided on each side, through which the propeller could be observed, and the atmospheric pressure was removed from the surface of the water by an air pump; under this condition the only forces tending to prevent cavitation were the small head of water above the propeller, and capillary attraction.

In the case of a propeller of two inches in diameter, cavitation commenced at about twelve hundred revolutions, and became very pronounced at fifteen hundred. Had the atmospheric pressure not been removed, speeds of twelve thousand and fifteen thousand respectively would have been necessary.

Photographs were taken with a camera made for the purpose, with a focal plane shutter giving an exposure of about one thousandth of a second, the illumination being by sunlight concentrated on the propeller from a twenty-four-inch concave mirror.

Photographs were also taken by intermittent illumination of the propeller from an arc lamp, the arrangement consisting of an ordinary lantern condenser, which projected the beam on to a small concave mirror, mounted on a prolongation of the propeller shaft, the reflected beam being caught by a small stationary concave mirror at a definite position in each revolution and reflected on to the propeller. By this means the propeller was illuminated in a definite position at each revolution, and to the eye it appeared as stationary. The cavities about the blades could also be clearly seen and traced, the photographs being taken with an ordinary camera and about ten seconds’ exposure.

A series of experiments was also made with model propellers in water at and just below the boiling point, dynamometric measurements being taken of power and thrust with various widths of propeller blade, the conclusion arrived at being that wide and thin blades are essential for fast speeds at sea, as well as a coarse pitch ratio of propeller.

The first vessel fitted with steam turbine machinery was the Turbinia. She was commenced in 1894, and, after many alterations and preliminary trials, was satisfactorily completed in the spring of 1897. Her principal features are: Length, one hundred feet; beam, nine feet; five-foot draught of water under the propellers; forty-four tons and a half displacement on trial; she is fitted with a water-tube boiler of eleven hundred feet total heating surface, and forty-two square feet of grate area, with closed stoke-holds supplied with air from a centrifugal fan mounted on a prolongation of the low-pressure turbine shaft. The engines consist of three compound steam turbines, high pressure, intermediate, and low pressure, each driving one screw shaft; on each of the shafts are three propellers, making nine in all; the condenser is of the usual type, and has four thousand square feet of surface.

When officially tested by Professor Ewing, F. R. S., assisted by Professor Dunkerley, she attained a mean speed on a measured mile of thirty-two knots and three quarters, and the consumption of steam for all purposes was computed to be fourteen pounds and a half per indicated horse power of the main engines. Subsequently, after some small alterations to the steam pipe, she was further pressed, and is estimated to have reached the speed of thirty-four knots and a half. She was, and still is, therefore, the fastest vessel afloat; she has been out in very rough weather, is an excellent sea boat, and at all speeds there is an almost complete absence of vibration.

In the Turbinia the exceptional speed results principally from two causes: 1. The engines, screws, and shafting are exceptionally light. 2. The economy of steam in the main engines is greater than usual.

At full speed the steam pressure in the boiler is two hundred and ten pounds; at the engines, one hundred and seventy-five; and the vacuum in the condenser twenty-seven inches, representing an expansion ratio in the turbines of about one hundred and ten after allowance has been made for wire-drawing in the exhaust pipe.

The first vessels of larger size than the Turbinia to be fitted with steam turbine machinery are the torpedo-boat destroyer Viper for the British Government, and a similar vessel for Messrs. Sir W. G. Armstrong, Whitworth & Company.

These vessels are of approximately the same dimensions as the thirty-knot destroyers now in her Majesty’s service, but have slightly more displacement. The boilers are about twelve per cent larger, and it is estimated that upward of ten thousand horse power will be realized under the usual conditions, as against sixty-five hundred with reciprocating engines.

The engines of these vessels are in duplicate. Two screw shafts are placed on each side of the vessel, driven respectively by a high- and a low-pressure turbine; to each of the low-pressure turbine shafts a small reversing turbine is permanently coupled for going astern, the estimated speed astern being fifteen knots and a half, and ahead thirty-five knots; two propellers are placed on each shaft.[G]

[G] On her second trial trip the Viper attained a mean speed of 34.8 knots, her fastest trial being over 35 knots, or about 41 statute miles per hour, with an indicated horse power of 11,000. This vessel is of about 350 tons displacement.

The latter of these two vessels has commenced her preliminary trials, and has already reached a speed of thirty-two knots. The manipulation of the engines is a comparatively simple matter, as to reverse it is only necessary to close one valve and open another, and, owing to there being no dead centers, small graduations of speed can be easily made.

In regard to the general application of turbine machinery to large ships, the conditions appear to be more favorable in the case of the faster class of vessels such as cross-Channel boats, faster passenger vessels, cruisers, and liners; in such vessels the reduction in weight of machinery, as well as economy in the consumption of coal per horse power, are important factors in the case, and in some vessels the absence of vibration, both as regards the comfort of passengers, and in the case of ships of war permitting greater accuracy in sighting of the guns, is a question of first importance.

As regards cross-Channel boats, the turbine system presents advantages in speed, absence of vibration, and, owing to the smaller diameter of the propellers, reduced draught.

As an instance, a boat of two hundred and seventy feet length, thirty-three feet beam, one thousand tons displacement, and eight feet six inches draught of water could be constructed with spacious accommodation for six hundred passengers, and with machinery developing eighteen thousand horse power; she will have a sea speed of about thirty knots, as compared with the speed of nineteen to twenty-two knots of the present vessels of similar size and accommodation.

It is, perhaps, interesting to examine the possibilities of speed that might be attained in a special unarmored cruiser, a magnified torpedo-boat destroyer of light build, with scanty accommodation for her large crew, but equipped with an armament of light guns and torpedoes. Let us assume that her dimensions are about double those of the thirty-knot destroyers, with plates of double the thickness and specially strengthened to correspond with the increased size--length, four hundred and twenty feet; beam, forty-two feet; maximum draught, fourteen feet; displacement, twenty-eight hundred tons; indicated horse power, eighty thousand; there would be two tiers of water-tube boilers; these, with the engine space, coal bunkers, etc., would occupy the whole of the lower portion of the vessel; the crew’s quarters and guns would be on the upper decks. There would be eight propellers of nine feet in diameter revolving at about four hundred revolutions per minute, and her speed would be about forty-four knots.

She could carry coal at this speed for about eight hours, but she would be able to steam at from ten to fourteen knots with a small section of the boilers more economically than other vessels of ordinary type and power, and, when required, all the boilers could be used, and full power exerted in about half an hour.

In the case of an Atlantic liner or a cruiser of large size, turbine engines would appear to present some considerable advantages. In the first place they would effect a reduction in weight of machinery and some increase in economy of fuel per horse power developed, both thus tending either to a saving in coal on the one hand, or, if preferred, some increase in speed.

The advantages are, however, less pronounced in this class of vessel on account of the smaller relative power of the machinery and the large quantity of coal necessary for long voyages, but the complete absence of vibration at all speeds, not to mention many minor considerations of saving in cost and reduced engine-room staff, are questions of considerable importance.

A SURVIVAL OF MEDIÆVAL CREDULITY.

BY PROFESSOR E. P. EVANS.

[_Concluded._]

In the seventeenth year of her age Miss Diana Vaughan joined the Freemasons, entering the lodge (“triangle”) of “The Eleven Seven,” at Louisville, and passing rapidly through the different grades until the “Elect Palladistic Knighthood” was conferred upon her after she had given satisfactory proofs of her Luciferian orthodoxy. One thing she refused to do--namely, to stab the host with a dagger--since this act implied a recognition of the sacramental character of the Eucharist. She maintained that there would be no sense in piercing the consecrated wafer unless it was believed to be the real body of Christ; but as she rejected the doctrine of transubstantiation as a childish superstition, she was unwilling to make a fool of herself by assaulting a piece of ordinary bread with a show of wrath. She would not hesitate to commit sacrilege, but did object to being silly. This scruple, or rather this lively sense of the ridiculous, rendered her unpopular with the Freemasons, inasmuch as it marred the performance of their most important and impressive Satanic ceremony, and thus gave her rival, Sophia Walder, an advantage, which she was quick to improve.

We need not follow the career of Sophia Walder, known to the infernals as Sophia Sapho. She is said to have been born in Strasburg, September 29, 1863, as the supposititious daughter of a Protestant parson, Philias Walder, and a Rosicrucian dame, Ida Jacobsen, with whom the clergyman lived after having murdered his wife in Copenhagen. Her real father, however, was the devil Bitru, who declared her to be the predestined great-grandmother of antichrist. In 1896, while in Jerusalem, she gave birth to a daughter, the grandmother of antichrist; this child was also of demoniac paternity. Owing to her uncompromising Luciferianism, she was a favorite of the Freemasons, and excited the jealousy of Diana Vaughan, who tells with zest of the practical jokes played on her. Thus, at a banquet of the Freemasons, somebody put a few drops of Lourdes water in her glass of lemonade, which caused terrible pain and threw her into spasms, from which she finally found relief by vomiting fire. This incident is cited by a Catholic writer, Dr. Michael Germanus,[H] in his Secrets of Hell (_Geheimnisse der Hölle_), as conclusive proof that “Sophia was possessed.”

[H] Michael Germanus (a Latinization of “_Der deutsche Michel_,” the personification of the German nation, analogous to the English “John Bull” and the American “Brother Jonathan”) is the pseudonym of a priest, Parson Künzle, of Feldkirch, in the Tyrolese Voralberg.

Bitru’s proclamation of Sophia Sapho as the prospective great-grandmother of the incarnate antichrist is given in full. It was dictated in Latin by Bitru at a meeting of Freemasons in Italy, and written down by Luigi Revello, and bears the devil’s signature, composed of Satanic signs and symbols, darts, sword, cords, lightning, bugle-horn, trident, and crowing cock.

This climax of absurdity ought to have served to expose the trickery and trumpery of the whole affair, but it produced the very opposite effect. Dr. Germanus refers to “Bitru’s sign-manual as highly interesting,” and characterizes “the documentary evidence as thoroughly convincing”; those who refuse to recognize the truth in the face of such positive proof he accuses of imitating the ostrich and willfully shutting their eyes to the light.[I]

[I] A photographic reproduction of this document is given in Diana Vaughan’s biography of the Italian statesman Crispi, which contains numerous illustrations and portraits of Crispi, Mazzini, Lemmi, Garibaldi, Giordano Bruno, and other “Palladists,” or Masonic worshipers of Satan. The original French title of the book is “Le 33ᵉ ⁂ Crispi. Un Palladiste Homme d’État démasqué. Biographie documentée du Héros depuis sa Naissance jusqu’ à sa deuxième Mort. Par Miss Diana Vaughan.”

The salvation of Diana Vaughan is described as due to her intense admiration for Joan of Arc, a feeling which was ardently fostered by the priests with whom she chanced to come in contact. One day, as she was attended by Asmodeus, Astaroth, Beelzebub, and Moloch, incarnate in “the counterfeit presentment” of fine gentlemen, she obeyed a sudden and irresistible impulse to invoke the Maid of Orleans, when these devils were immediately stripped of their disguise, and stood before her in their true character as imps of hell, with hoofs and horns, and emitted an intolerable stench. No sooner did they perceive that they were unmasked than they vanished with a fearful howl. This miracle made a deep impression upon her, and led to her conversion. She took refuge in a Parisian cloister, and, after severe penance and proper instruction, was received into the bosom of the Catholic Church. During this period of penitential seclusion she wrote her Memoirs, which produced an immense sensation in clerical circles, and were pronounced by a high ecclesiastical dignitary to be “worth more than their weight in gold.”

It must be confessed that in weaving this tissue of fabrications Taxil showed consummate skill as a romancer and a profound knowledge of the possibilities of human credulity. He made a happy hit in calling the heroine of his Stygian story Diana, since in the annals of witchcraft the pagan goddess of the chase is wont to frequent the nocturnal assemblies of demons, and in mediæval theology the phrase “_congressus Sabathi cum Diana_” was a common expression for intercourse with Satan. Another masterly stroke was to represent her deliverance from the snares of evil spirits and the hallucinations of Luciferianism as a miracle of grace wrought through the mediation of Joan of Arc, thus furnishing an argument in favor of the canonization of the Maid of Orleans, which the cleverest _advocatus diaboli_ would be unable to answer. At this time Taxil prepared also a Catholic prayer book entitled _Eucharistic Novena_, published under the name of Diana Vaughan, and containing forms of supplication against unbelief, worldly indifference and lukewarmness, hardness of heart, blasphemy, and unchastity. The covert sarcasm which pervades the entire manual of devotion comes out most clearly in the section on the violation of the seventh commandment. A copy of the work, which had been approved by the Archbishop of Genoa, was sent to Cardinal Parocchi, with a letter signed “Your Eminence’s most devoted servant in Jesus, Mary, and Joseph, Diana Vaughan,” and five hundred francs, of which two hundred and fifty were to be used for organizing an international antimasonic congress, and the rest to be given as Peter’s pence to the Pope. The cardinal replied with great cordiality to his “dear daughter in our Lord,” called her conversion “one of the most glorious triumphs of grace,” and added, “I am reading at this very moment your Memoirs with burning interest.” He gave her his blessing, and conveyed “the thanks and special benediction of his Holiness.” Numerous letters of a like character were received from the Vatican. On May 27, 1896, the General Secretary of the Apostolic See, Verzichi, wrote that “his Holiness had read her _Eucharistic Novena_ with extreme pleasure”; two months later the Pope’s private secretary, Vincenzo Sardi, thanked her in the name of Leo XIII for her exposure of Crispi, and bade her “continue to write and to unmask the godless sect,” and the _Civiltà Cattolica_, the official organ of the papacy, praised her “inexhaustibleness in precious revelations, which are unparalleled for their accuracy and usefulness. Freemasonry is confounded, and seeks to evade the blows of the valiant championess by denying her existence, and treating her as a myth. It is a pitiable shift, but Freemasonry can find no better refuge.” “Your pen and your piety,” wrote Monsignore Villard, October 15, 1896, “are predestined to demolish the foes of mankind. The good works of the saints have always met with opposition, and it is no wonder, therefore, that yours should be combated.”

Naturally, there was intense curiosity to see this new convert and powerful defender of the faith. This inquisitiveness was easily allayed at first by the plea that the cloister to which she had retired must be kept secret, in order that she might be safe from assassination by the Freemasons. Meanwhile the medium of correspondence was a bright American girl, employed as copyist in a Parisian typewriting establishment, who wrote all the letters at Taxil’s dictation, and received a monthly salary of one hundred and fifty francs for her services. After a time he deemed it politic to introduce her privately to select circles of Catholics, who were thereby enabled to testify to her existence, since they had seen and conversed with her. The following incident may be mentioned to illustrate the adroitness with which she played her part: M. Pierre Lautier states that he once breakfasted with her, and offered to pour a little Chartreuse into her coffee, but she refused it with a singular sign of aversion, and took a few drops of old cognac instead. As an ex-Luciferian, she instinctively shrank from a drink made in a cloister, or what she called “an Adonaïc liquor.” That she should have thought of such a feint on the spur of the moment indicates that she had not only made a thorough study of her rôle, but also had been endowed by Nature with genuine theatrical talent. A full account of the solemn sham, published in the _Revue Mensuelle_, served to strengthen the faith of waverers in the reality of Diana Vaughan, and furnished an admirable opportunity for discoursing on the difficulty of throwing off Satanic influences; for here was a young lady who, although she had received absolution and thus become a child of grace, could not forget the terrible effect of a few drops of Lourdes water on one of her former demonolatrous associates, and recoiled with horror from a glass of Chartreuse. Taxil and his confederates confess that they often “doubled up with laughter” over the success of their imposture, and indulged in jokes about it in their writings. Thus Dr. Bataille, in the first volume of The Devil in the Nineteenth Century, remarks, as a peculiarity of Diana Vaughan, that she “is very fond of wearing male attire,” but no allusions of this kind, however pointed, seemed to have excited any suspicion of guile in minds predisposed to credulity by Nature and by education.