ACTIVE TYPE OF STABILIZING GYRO. 227 



In Mr. Norden's discussion we are given a number of important facts on the 

 general subject. He brings out the results of his investigations relating to efficiency 

 of stabilizers and shows that the new device leaves very little to be desired on this 

 important point. He also calls attention to a very important and significant 

 features of this new system of stabilization, viz., that when the angular velocity 

 of a ship is held down to practically o, practically o work is expended in holding 

 it; in other words, when the ship is held practically free from rolling it has been 

 found in practice and has been thoroughly demonstrated to require very little 

 power to maintain this condition. This is an original proposition toward which 

 I have been working and was first set forth and discussed by me a number of years 

 ago, and though it may at first sight seem revolutionary it is nevertheless true, 

 and being true it should work nothing short of a revolution in our methods of 

 stabilizing ships, and it also emphasizes the fact that there now remains no reason 

 why ships should roll at sea. 



My acknowledgments are also due to Naval Constructor David W. Taylor 

 and many of his brother officers who contributed largely to the success of the work ; 

 and also to Carl L,. Norden, M. E., who has been actively associated on the work. 



The President: — I am sure you will all agree with me that the Society is 

 indebted to, and now gives its thanks to Mr. Sperry for his paper on the Stabilizing 

 Gyro. 



We will now proceed to the paper entitled ' ' Notes on Fuel Economy as Influ- 

 enced by Ship Design," by Mr. E. H. Rigg, Member of the Society. 



Mr. E. H. Rigg, Member: — In view of the fact that the reading of papers is 

 desired to be limited to a short briefing of them, in order that the discussion may 

 be opened, I will read but a small resume. 



Mr. Rigg presented his paper, and after the reading of it said: "I should like 

 to add that I have recently been very much interested in reading the report of a 

 lecture given in London before the Royal United Service Institution on ships of the 

 Monitor class, that is, ships with longitudinally corrugated sides. Of course I 

 have no definite information on this subject, but from the reports of the lecture it 

 appears that a reduction of 15 per cent indicated horse-power is claimed for these 

 corrugated sides. I think this type of vessel should be added to the examples given 

 in this paper, because here is most decided economy due to ship form. 



