MIRACLES OF SCIENCE 



German make. It is pretty obvious that the non- 

 magnetic compass is the compass of the immediate 

 future. 



The actual Sperry gyro-compass, as adjusted deep 

 in the hull of a battleship, is an electrically rotated 

 steel wheel about twelve inches in diameter. The 

 mechanism of the master compass is of course con- 

 cealed within casings, and a compass card of familiar 

 appearance is adjusted at its face. There is a pneu- 

 matic damping system to minimize the disturbances 

 due to motion of the ship. There are also automatic 

 correction dials, which must be adjusted for the lati- 

 tude and for the speed in knots from time to time. 

 But these may be adjusted as easily as you set a 

 watch, and aside from this the mechanism requires no 

 alteration. The force with which the gyro-compass 

 resists deflection from the true north is almost three 

 hundred times the directive force of the most power- 

 ful magnetic compass. 



Any number of small "repeating" compasses, con- 

 nected by wire with the master compass, may be dis- 

 tributed about the ship. These are not properly 

 speaking compasses in themselves; but their dials 

 which may be placed in any convenient position, hor- 

 izontal or vertical or slanting duplicate accurately 

 the record of the gyro-compass. 



STEADYING SHIPS AT SEA 



This use of the gyroscope to take the place of the 

 magnetic needle is one of the newest developments 

 of applied science. But there are other applications 

 of the gyroscopic principle that are less novel. More 



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