THE SPERRY GYRO-COMPASS IN SERVICE. 293 



also in the navigation of the ship. No difficulty was experienced in keeping 

 it in fine running order. In fact the electrician who was charged with the 

 care of the apparatus had also to give his time to keeping in order all of the 

 fire-control and telephone systems on the ship. A few minutes a day devoted 

 to the compass were all that were necessary. After the compass had been in 

 operation on board the ship for two or three months, Mr. Sperry came aboard 

 to inspect it and to observe its operation in target practice. During that 

 time complete tests were made of the operation of the instrument under 

 shock of gunfire, rolling and other disturbing influences, with satisfactory 

 results in every case. 



The satisfactory performance on the Delaware resulted in a contract for 

 supplying the Navy with eight complete gyro-compass outfits. These were 

 installed on board the U. S. S. North Dakota, Florida, Utah, Michigan, 

 Arkansas, and Wyoming, and on the submarines K-i and E-2. 



The design of these instruments differed quite considerably from that of 

 the experimental compass. They were installed under the supervision of 

 Mr. Sperry and his engineer, Mr. Ford, and were kept under constant obser- 

 vation so that any defects which might develop could be corrected and the 

 design of the instruments so changed as to prevent the recurrence of the 

 defects. Because of the necessary small changes in the instruments it was 

 impossible to issue instructions as to their care and adjustment. For this 

 reason these first compasses labored under a considerable handicap. Con- 

 sider, for instance, what the fate of the magnetic compass would be if it were 

 placed on a steel ship where those in charge of it knew nothing of its theory 

 or the methods used for its compensation. This was the position in which 

 the first gyro-compasses were placed. So far as the ultimate development 

 of the instrument is concerned, this handicap served a useful purpose by 

 developing an instrument requiring no expert knowledge and no attendance. 

 However, notwithstanding the fact that the instrument was new and those 

 in charge of it had no means of learning much about it, it was successful 

 from the first. 



Of course many small defects developed in the operation of these first 

 eight instruments. None of these defects was fundamental in character and 

 they were all corrected as soon as they occurred. In the latest instruments 

 every one of these defects has been completely eliminated. 



With very few exceptions it was found that by devoting ten or iifteen 

 minutes a day to the compass it could be kept in perfect condition and could 

 be used as a reliable navigating instrument to the exclusion of the magnetic 

 compass. 



One of the officers of the U. S. S. Florida told the author of an incident 



