GERMAN GUN BOGEY.

Pukekohe & Waiuku Times, Volume 5, Issue 167, 20 April 1916, Page 4 (Supplement)

GERMAN GUN BOGEY.

A NAVAL SCARE-MONGER'S

NONSENSE.

It has been said that in their prosecution of the war the Allies have shown -themselves to be destitute of initiative. The Kaiser is reported to have sneered contemptuously—"Not one of the Allies . Jias a single idea in his head." We may lack imagination and initiativ>. but the charge ought never to be laid against -us that we are devoid of an amazing .fertility of genius in conceiving miraculous Jules Vernes projects, which we -every day impute to the eneir.y's preparations against ourselves. It is possible we might long since have won the war if that wealth of fancy, displayed -in accrediting to Germany new and aw:sul schemes of destruction, had been inverted and applied to the solution of -our own war problems. We suffer from .a plethora of misdirected genius. It is too bad to allege that we softer from •destitution of ideas; the Kaiser cannot •iiave read those articles, penned by our scare-making critics, who, "in a position of greter freedom and less i espons.Tnlity," as Mr. Gladstone teimed 1 Hie Opposition Benches, lavish such enconiums upon the administrative genius of Army and Navy. One of the bogeys perpetiiallj flaunted in our eyes by the denizens of these imaginative regions is the awful things which Von Tirpitz is secretly preparing within the seclusion of the Kiel Canal for the destruction of the British Fleet -when he emerges for "the Day." This liogey has been again resuscitated by an able journalist—unfortunately for

his reputation in naval matters —in the time-worn garb of the secret re-arma-ment of the German Navy wibn colossal 17-inch guns, which are to blow the British Navy into smithereers. This is a particularly insidious form of seare•mongering. The British natm is very -" getatable" on the Navy; the appeal to our curiosity and credulity is thereby accentuated. "Ah! the hidden dogs: 1 was sure they were up to some game all the time: what's our Navy oeen doing?" That's how our wiseacres view it. The scare has on this occasion received the imprimatur of a question in Parliament, begging for assurances officially that the British Navy is really not to be caught napping anc is prepared for this danger of the re-arma-ment of the German. WHAT THE CRITIC IGNORES. It is not ungenerous to say that a --critic who ventures this nonsense, un--diluted by sensible qualifications, enters upon a subject charged with profundities which he elects to ignore. Superficially, the substitution on battleships of a 12-inch weapon by one of 17 inches is as easy as Paddy's descrip--tion of the manufacture of a big gun—- " Take a long hole and pour brass round it." And it is scarcely less exact. The .-slightest acquaintance with the technicalities involved would have prevent--ed the critic rushing in where an expe-t would have feared' to tread. It is our purpose here to exhibit some of the •unexplained difficulties ignored by the •critic, and review these with past experiences on warship construction. This is the hest way to dispose of the theory » and annul the fears it may have engendered amongst the public. A cursory acquaintance with the various types of Dreadnoughts in the British and German Navies would have convinced our friend that with every development in gun power there is a corresponding development in the size, ■width, and displacement of the ship itself. The change from a smaller to a larger calibre of gun involves many •questions for the naval architect. An increased size of gun—particularly Buch a large development as that propounded in the case of the German Navymeans vastly increased weignt to be carried in the upper works. The centre ■of gravity of the ship is raised ; its stability is affected; the periodicity of rolling'in heavy seas is altered: the steadiness of the ship as a gun platform for accurate firing is disturbed'. The "sinkage" of the vessel is likewise seriously .altered: the strain on the framework, by the firing of the heavier weapons, is no less seriously increased. In the substitution of a 12-inch gun by one of 17 inches every one of these important -questions is involved. The result may he imagined; but let us loo'% first at some of the blunders in the designs of warships that have actually occurred in the past through miscalculation of weights. And increased weight on the superstructures is one of the objections to the plan suggested. Thirty years ago two vessels, known .as the Warspite type, were designed for • cruising purposes in Colonial seas. When launched they floated eleven inches deeper than the water i ne calculated. A serious mistake in allowances for weights had been made; the ves- . sels wer € useless. Would the blunder committed there be worse than that of

the designer wno proposed to suosuuue ten guns, weighing in the aggregate 600 or 700 tons more than those displaced, in the upper works of a ship? SOME VITAL POINTS. On the authority of the late Sir Wm. "White, the designer of the battleships preceding the Dreadnought era, the "sinkage" of our "Dreadnought" from normal draught to deep load' is no less than five feet. The connundrum befoie our critic is to explain what the effect on the "sinkage'' of the German battleships would be.by adding COO or 700 tons to the weight of their si perstructures. One begins to see on what thin ice he has skated himseli'. t-, not the danger present —and many more probably even more critical—that the whole armour belt of the vessels so altered would be immersed below the water line and that what might accordingly be gained in offensive powers would' be lost in defensive? A further source of trouble would arise from the greatly increased size of the bigger 17-inch guns. A 46 calibre 17-inch gun would measure 73 feet ;n length, while the displayed 50 calibre 12-inch gun measures only 50 feet. Now the situation of the turrets in these German battleships, their rotation and arcs of training for firing the guns, was calculated and devised on the basis of weapons 50 feet long. What difference will the 73 feet guns make to the rotation of the turrets and the arcs of train- ■ ing? What interference with the firecontrol stations; what relation will they exert on the habitabilti, - of the navigating bridges? A ship 's designed all of a piece, every detail scientifically fitting in with the rest. You can not play smash with one feature without destroying all, any more than you can substitute the first violins in an orchestra by double basses. The Queen Elizabeth" with her 15-inch guns, and carrying only eight of thevn in four turrets, is 20 per cent, longer than the original Dreadnought with five turrets carrying ten 12-inch gun.?, and displaces 10,000 tons more. These increases were not added for "fun." FATAL FIRING STIUTN. But we still have an ugly problem to face —the question of the strain on the framework of the vessel imposed by the increased power of the 17-inch guns. "Thn <?norgy developed by a 12-inch fifty .-alibre gun is about 50,0ft0 foot tons.

The recoil, according to Newton's law of equal reaction, is just this torce also; it is the strain borne by the ship. When she fires all her ten guns in salvo —"a broacside" —the total energy developed is 500,1)00 foot tons; we shall explain this technicality later. The energy developed by a 15-inca gun is, however, 90,000 foot tons. For a 17mch naval gun we have no di.ta; but one would not be far out in stating it at 130,000 toot tons. For a broadside of ten guns —the German shns have all ten guns accordingly 1,300,000 foot tons.

This is where the crisis of our critic's theory arives. The structural framework of the battleships were designed to stand a strain of 500,000. plus marginal safety; but he proposes to give them 1,300,000 foot tons, or an increase of 160 per cent .over calculated strain. The average reader will unaerstancj what this increase is when it ,s stated roughly as the force generated by forty Dreadnoughts of 20,000 tons each falling through a space of one foot. Quite a trifle —to be absorbed, probably by placing cotton wool aboard so easy does our critic view such matters. Ask any bridge builder, ask the builders of the Forth Bridge, whether they would guarantee a sudc.cn additional strain of 800,000 foot tons over an am as limited as the five turrets of a battleship. It is not disclosing any State secret to say that notwithstanding all his calculations and allowances for marginal safety, the naval architect has sometimes gone wrong in allowing for the strain of gunfire on battleships. _ Occasionally, afer initial gun practice, a battleship has to be returned to the bui'der for "stiffening." We could mention some important battleships which have required this attention even where the architect has made all calculated provision for strain. What of increasing the calculated strain by 160 per cent. ? Then the placing of so much extra weight high up in the vessel would render her topheavy, ana increase her oscillation or " roll" in heavy seas, with the result that the gunners would issue forth from the Kiel Canal on a vessel of whose characteristics in this essential they were entirely :gnora>.t. The " hj'phenated" German 1 attleship would emerge simply to find 'tself in "Queer Street" —if not worse, lor we recall an instance in the early days of the ironclads, immediately following the "converted" Royal Sovereign, where one turned turtle in a storn, and was lost with all on board.

As a matter of fact, if the business were as easy as our critic considers, the British/ the Japanese, and many other navies, with splendid but now obsolete pre-Dreadnoughts, would have indulged also in re-armament with heavier guns long ere now. But no navy has attempted it. The reason is self-evident.