214 ACTIVE TYPE OF STABILIZING GYRO. 



Should we select a larger maximum stress for the wheel, then the gyro 

 plant is considerably decreased over the above figures. This wheel can 

 easily be made to give nearly double the roll quenching power. 



Even in this extremely stiff ship, requiring relatively an unusually heavy 

 gyro, the differential as to both weight and space stands out in favor of the 

 gyro in marked contrast to the tanks. This is especially true when it is 

 understood that the tanks will only function or perform half, and the more 

 unimportant half, of the work easily performed by the gyro; that is, the tanks 

 are only serviceable for stabilizing, whereas the gyro is originally intended 

 for producing roll in the ship to prevent the ship from being caught in the 

 ice or freezing solid in the process of forcing her way through heavy ice 

 fields and especially wind row ice during the winter and spring months. 

 For this latter purpose, however, it is found that a small gyro will perform all 

 those functions, that is, the gyro illustrated here, while ample for stabilizing 

 the ship, is much larger than is required for rolling. The gyro illustrated 

 would only require to be run at one-third or one-half speed for the production 

 of all the rolling that could ever be required by the Ashtabula in breaking 

 through the heaviest ice. This is owing to its incessant action developing 

 its full force in proper direction and with the proper emplacement upon each 

 half period. Very heavy rolling can easily be produced and maintained. 

 The action under these conditions is far simpler than in preventing roll, 

 inasmuch as the reaction of the ship after rolling has started is found to 

 react back to the gyro sufficiently to automatically control its precessional 

 movements ; usually in rolling only fractional speeds of the gyro are used. 



Not the least interesting in connection with the Worden equipment 

 were some gyroscopic pendulums employed in obtaining records of the 

 motions of the Worden. These recorders were originally designed by the 

 author to represent pendulums (though they are actually less than a foot 

 in height) of very great pendulous length, namely, i ,000 miles, representing 

 an artificial mass moment of i| tons hung from the distance. In the earlier 

 trials of this instrument it was found that there existed no necessity for so 

 long a pendulum and this was afterwards reduced to the equivalent of a 

 ten-mile pendulum. The records were obtained by the gyros thus arranged. 

 In connection with this apparatus one point which is new and is of special 

 interest is the elimination in the records of the influence of extraneous 

 motion components reaching the instrument or influencing to the slightest 

 extent the record itself. 



For instance, if we are recording the roll of the ship it is desirable that 

 all motions relating to either the pitch or yaw or other azimuth movements 

 should be eliminated and the apparatus be entirely free from disturbances 



