The Giant Crane of the Austrian Navy 



It has a three-hundred-foot jib and while handling a load maintains 

 its equilibrium by means of water let into the rear ballast tanks 



AT work in the Austrian Navy Yard 

 at Pola is the largest floating crane 

 in the world. A giant floating crane 

 is this, with its normal lifting capacity of 

 two hundred and forty tons. It thinks 

 nothing of taking guns and turrets weighing 

 sixty tons more than that and carrying 

 them to the ships under construction about 

 the yard. 



Nothing about the ship is nearly as im- 

 portant as this busy crane. The other 

 cranes of one hundred and one hundred 

 and fifty tons capacity — wonderful cranes 

 a few years ago! — have been relegated to 

 the minor jobs of the yard. 



The barge crane is commanded by a 

 captain who stands at the navigating 

 bridge. From his point of vantage, he 

 signals the engineer at the hoisting engine 

 to run out the cable truck on the jib and to 

 let down the cable to the wharf. When the 

 load — gun, or whatever it may be — is 

 secured upon the grappling hook, the 

 captain has it raised to the top of the jib, 

 one hundred and eighty-seven feet in 

 the air. Before the load has ascended 

 many feet, he will have signaled to the 

 boiler room just below the deck, and the 

 barge will be steaming away towards the 

 ship it is to equip. There she drops anchor 

 and "straightens to" on tightening her 

 anchor cables by her modern steam capstans. 



With her mighty three-hundred-foot jib, 

 the crane can run her burden far over the 

 side of the largest battleship. While 

 this is going on, water is let into the 

 rear ballast tanks of the barge. Finally, 

 when the load has been deposited on the 

 battleship, this water will be forced out 

 again with compressed air to restore the 

 equilibrium of the barge. 



This diligent little ship keeps constantly 

 in touch with the yard headquarters by 

 means of the auxiliary patrol boat that is 

 assigned to her. Instructions reach the 

 barge captain through the wireless station 

 on board the patrol. It is through these 

 channels that orders come when a subma- 

 rine meets with mishap during its opera- 

 tions on the Adriatic Sea. 



If the submarine has foundered within 

 any possible reach of the land, the barge is 

 ordered to drop whatever work it is doing 



and to follow the fast patrol boat to the 

 scene of the disaster. Expert divers put 

 off from the yard to meet the barge on its 

 way to the sea. Reaching the point where 

 the submarine has been reported to have 

 gone down, the divers at once descend, 

 carrying the two lifting cables with them. 



If the divers are fortunate and find the 

 submarine, the grappling hooks are at- 

 tached to the emergency eyes at each end 

 of the U-boat's hull. Then, with the two 

 lifting cables working together, the U-boat 

 will be raised towards the surface at the 

 rate of about three feet a minute. The 

 rear cable, which goes through the hole 

 built into the front deck of the ship, cannot 

 lift its end of the submarine entirely out of. 

 the water. The front cable can, however, 

 and it raises the boat until its conning- 

 tower clears the water. In this way, the 

 crew are enabled to escape. 



American cranes are of a more specialized 

 type, and of an extraordinary efficiency. 

 Revolving jibs take the place of the station- 

 ary ones of the Austrian craft. Instead of 

 having to maneuver to aline the barge in 

 order that a load may be lowered into exact 

 position, the American cranes maneuver 

 the jib around. 



On our floating cranes, moreover, the 

 driving machinery is electrical. The oper- 

 ator is stationed in a house near the bot- 

 tom of the jib. The house rotates with the 

 jib so that the operator can overlook every 

 motion. The electric motor controls, and 

 even the distant-controls for the electric 

 capstans are mounted on the switch- 

 boards in this cabin. By co-ordinating his 

 movements, one man can handle his barge 

 with marvelous facility. 



Hence, where Austria's cranes exceed 

 ours in size, the American cranes excel in 

 dexterity. Furthermore, the use of water 

 ballast to prevent a barge from tipping 

 frontward when a load is on the jib seems 

 absurd to American engineers. Our barges 

 are inherently stable. The crane is 

 mounted so near to the center of the ship 

 that twice the capacity load would not 

 overturn it. No, we do not use water 

 ballast — the cables might break some day 

 and as the load falls off in front the ballast 

 might tip the barge over at the rear! 



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