ACTIVE TYPE OF STABILIZING GYRO. 



By Elmer A. Sperry, Esq., Member. 



[Read at the twentieth general meeting of the Society of Naval Architects and Marine Engineers, held in 



New York, November 21 and 22, 1912.] 



The navies of the world, in the struggle for supremacy, are making for 

 maritime progress as no other force could. These developments, considered 

 strictly from the present-day standpoint of conservation, more than justify 

 the entire expenditure, and though remaining for a time in the possession of 

 one nation, soon become world property. Our own navy has been in the fore- 

 front of this progress. Consider the recent great advancement of knowledge 

 on the relation between form-line, speed and power of ships ; very largely the 

 product of our own model tank at Washington, due to the broad policies and 

 wonderful foresight of our navy and the rare ability and devotion of its 

 personnel. The marked reduction in fuel, in many instances halving the 

 fuel requirements in marine transportation, is certainly a proud monument 

 to any navy and one our own nation should be proud of. And this is only 

 one of its achievements, all accomplished so quietly that the nation does not 

 realize nor appreciate it as do the more maritime nations over the seas. 

 These may all be considered as "by-products," simply incidental to the real 

 development or the real significance of the navy in its relation to our place 

 among the nations. 



The engineers of our navy have been responsible for numerous advances 

 in power and fuel economy, not only by establishing efficient and scientific 

 methods of managing boiler and engine plants, but also by numerous improve- 

 ments in the design of engine itself. 



The subject with which this paper deals is one that has received atten- 

 tion and has for some time been under investigation by the architects of our 

 navy. Two years ago I was permitted to touch upon some small portion of 

 this work; since that time the progress has been marked. In fact, with the 

 data now available, it is possible to design a stabilizing plant which will con- 

 fine the roll of a ship to almost any limit desired, regardless of the displace- 

 ment and period of that ship. The same type of plant may be used for 

 rolling the ship at will, which feature has an important application in our 

 icebound waters. 



It is felt that when the data relating to the active type of gyros is ready 



