46 RECENT PROGRESS WITH THE ACTIVE TYPE 



of the worm gear shaft engages the circular rack upon the precession frame, shown 

 in Fig. 7, Plate 32, so whenever the motor turns in either direction the precession 

 frame slowly tilts or oscillates to and fro upon its main gudgeons. The response to 

 slight angles in the ship's motion is found to be very complete — one person walking 

 from rail to rail actuates it — and practically without time lag. With each of these 

 tilts of the gyro very heavy gyroscopic moments are developed and delivered to the 

 ship simultaneously with and in opposition to each wave increment from the sea ; 

 these opposite forces cancel each other and, while this contest of forces goes for- 

 ward, the ship, with its ponderous mass which always requires time to take on mo- 

 tion, stands aloof and does not move one way or the other until one of these forces 

 conquers. The gyro is always victorious and the ship is thus actually given an in- 

 cipient roll in the opposite direction and the contact of the little controlling gyro 

 which initiated all of these movements is finally broken, the precession motor stops, 

 the brake is applied and the generator of heavy opposing gyro moments in that par- 

 ticular direction is brought to an end. The gyroscope itself is thus free and stands 

 ready to neutralize and quench the next wave increment or rolling increment which 

 usually arrives from the opposite side ofthe ship, whereupon the above cycle of 

 operations causes the gyro to automatically oscillate oppositely and effectually pre- 

 vents any roll beginning in the opposite direction. 



Inasmuch as all rolling of ships is due to an accumulation of individual wave 

 increments, and since each increment is checked and neutralized, as we have seen, 

 the ship never starts to roll and therefore never rolls. 



The plant works very smoothly and practically without noise and seems to per- 

 form its duty easily. A little reversing switch provided with nameplates plainly 

 marked "Rolling" and "Stabilizing" allows the stabilizer to be operated to roll the 

 boat at will. This is useful in working off from sand bars, mud banks, negotiating 

 ice packs, etc. In fact this has already been found extremely serviceable in the shal- 

 low waters of Toledo inlet. 



Other points that have been definitely settled by the operation of the stabilizer 

 are as follows: 



That under conditions of a strong wind which had been blowing all day, with 

 Government storm warnings hoisted all along Lake Erie, a trip was made from 

 Toledo to Cleveland, in the evening, where with the gyroscope "off" the ship rolled 

 up to 25° each side of the vertical, and with the gyroscope "on" this roll was quenched 

 down to an average of 3° or less, the interesting point being that the boat steered 

 very much steadier and made her run in as good time as on any previous trip, includ- 

 ing calm seas, and also while being stabilized her decks remained dry. 



The gyro being mounted right over the main saloon it was feared that the deck 

 would operate as a sounding board and the noise would be objectionable. This, 

 however, was not found to be the case. While one is conscious of some noise, es- 

 pecially in choppy and uneven seas, there seems to be no difficulty in carrying on an 

 ordinary conversation. There is no noise whatever in any of the staterooms aft. 

 It is gratifying to note also that the chief engineer and others who reviewed the 



