BERTHA CALLS ON PARIS

Cue (NZERS), Issue 18, 28 February 1945, Page 19

BERTHA CALLS ON PARIS

rnHE introduction of the flying bomb J and other devastating projectiles takes one back to a spring day nearly twenty-seven years ago when Paris witnessed a scientific " miracle " —one which everyone, inchiding the best scientists, said could not happen. On March 23, 1918, explosive shells from a mysterious source fell in the heart of the city.

To believe that they were fired from behind the German lines, 70 miles away, seemed almost as fantastic 7as to assume they had come from the moon. But the incredible soon had to be accepted as /fact.

Almost as astounding as the mysterious bombardment itself was the speed with which the French discovered the exact source of the shells. Within three hours after the first explosion French General Headquarters knew the approximate location of the guns (there were three carriages and seven guns) and within 30 hours French artillerymen were retaliating so accurately that the position of gun number one, which had fired the first shell, had to be abandoned.

When the first : explosion occurred near the Quai de Seine no one was injured; but 20 minutes later, a mile an a half away, a second explosion killed eight people and . wounded thirteen.

News of this disaster quickly spread O' all parts of the city, together with e wildest rumours. A common theory

was that the bombs had come from a new type of plane flying too high to be discovered. Others believed that German spies had captured pieces of French artillery and were firing from within the French lines. Explosions continued during the day at intervals of about 15 minutes, and planes of the Paris -Defence Service searched the sky for raiders. Soon ; military experts had rejected the idea of air bombs because when the projectiles struck buildings it was always on the north-east side. Presently, the theory of gun-fire was confirmed. A shell had passed completely through the wall of a building without exploding. It had also made a hole in the floor. These two holes gave the exact direction from which the shell had come, as well as the angle of its descent. Mathematicians could now plot the path of the projectile and determine approximately its starting point. The evidence pointed to a little comer section of the German front, about 75 miles from Paris, near the city of La on. Next, the investigators turned to their maps. Particularly good aerial photographs had recently been made of the Laon area . and these showed a little spur leading off from the railroad at a wooded spot near the place the calculation had indicated. The French had reason to think they were ” getting warm." Two heavy railway guns were ordered to Vailly where they began firing toward the

point where the big gun ought to be. Although they made no x direct hit, one French shell hit a tree near the number one gun, killing an officer and injuring six of the gun crew..

If a French spy could have wandered into that area he would have seen a giant gun, long enough to reach to the top of a 10-storey building, mounted on a huge steel frame-work 25 feet high. This and two others, built in the forest with the utmost secrecy, represented the culmination of two years’ work.

Early in 1916 Dr. Von Eberhardt, one' of Germany’s leading physicists, had convinced Director Rausenberger at the Krupp works that it would be possible to build a* gun capable of sending , an eight- projectile 60 miles. The seven guns finally constructed had a range of 80 miles. Though weighing hundreds of tons, each gun was made with the precision of a watch.

Almost as much care as went into the designing of the guns was devoted to concealing them. To begin with they’were' placed in St. Gobain Wood, the densest—forest available. Each of the three gun emplacements was reached by rail-road; but to mislead aerial observers a fake spur was built with the ties laid as conspicuously as possible. It was this spur which showed on the photographic maps and it was possibly reponsible for the failure of the French gunners to score -direct hits.

The railway spurs actually used were painstakingly hidden. Only those trees directly in the path were cut. and then the tops of the taller trees were drawn together with wire. . Small trees and saplings were placed between the ties, and the rails were covered with grass and brush.

In firing a gun of such proportions, ordinary artillery calculations were not nearly enough. Even astronomers were called upon for aid. Since the shell would be in the air three minutes, there had to be corrections for the rotation of the earth. Moreover, curvature of the earth had to be considered in

computing the exact distance of the target. Then there had to be the precise allowances for the density and temperature of the air, for the direction and velocity of the wind, and for the temperature of the powder. And because of the rapid deterioration from heat and erosion, each gun had to be sent back to the Krupp works for reboring after 50 or* .60 rounds. The 265 lb. shell left the gun under nearly a million pounds . pressure at a speed of nearly 3,600 miles an hour. As it , mounted into the rarefied atmosphere where air resistance was; less, it lost speed because of the pull of gravity until at 24 miles above the earth it was travelling at less than half its original speed. Then in its downward" course it picked up speed once again until it struck the heavier atmosphere near the earth, when it actually slowed down. When the number one gun was firing its first shots into Paris, the designers and the Kaiser were present as spectators. If they had been there a day or two later to see the opening shots of number three gun the course of history might have been modified, for the gun blew up and killed 15 men. , Apart from 256 lives lost and 020 persons wounded the material damage inflicted by the big guns was less than the three million pounds that they cost. What became of the big guns? The Germans managed to get them back to The homeland during the last retreat. No Allied officer or • soldier ever laid eyes on them, though one railway gun carriage was captured The Versailles Treaty provided that the - Germans should open all their war archives to the Allied intelligence services. But before the Treaty was signed the guns were all taken to the Krupp Works and; melted and a special law was hastily passed making it an act of treason, punishable by death, to disclose any data about them. Not until 1925, By the devious methods of espionage, did information about them fall into non-German han s. The information, when finally obtained, was fairly complete.