214 THE COMMERCIAL GYROSCOPIC COMPASS. 
The gyro-compass with its great directive power and repeater system affords 
the unique opportunity for operating still other devices which have been found 
of great service on shipboard. Not only can the gyro-compass actuate the auto- 
matic helmsman, which holds the ship with great precision and minimum helm, 
but it may also operate a recorder, which makes an automatic record of every 
change of heading, however minute, recording the exact moment of such change, 
thus giving a continuous and accurate record of the heading of the ship. This in- 
strument is incidentally useful in obtaining the characteristics of different helms- 
men, and its records are of the greatest value to the navigator, especially when ob- 
servations are impossible—navigating by dead reckoning. This new instrument 
is very simple, consisting merely of a repeater compass with an enlarged removable 
dial upon which the record is made by a recording pen operated by a small clinometer 
seen above the dial. This instrument is shown in Fig. 9, Plate 126. 
Figure 10, Plate 127, shows the comparison between the larger battle gyro- 
compass and the new destroyer or commercial compass, the latter being to the right. 
From service tests already had and all indications, the new commercial com- 
pass has justified the very considerable labor and expense involved in its develop- 
ment. 
The acknowledgment of the author is due to Mr. H. L. Tanner, who has shown 
wonderful persistence and ingenuity in overcoming the difficulties attendant on de- 
veloping the new gyro-compass in its simplified form, through work extending over 
a series of years. 
DISCUSSION. 
Tuer CHAIRMAN :—Your applause shows your appreciation of Mr. Sperry’s address and 
his paper. Does any one desire to ask him any questions? JI doubt if any one has any 
criticism to offer. Some may want to ask him questions. Possibly the naval officers pres- 
ent may have some observations to make. If not, this is the last paper to be presented, and 
completes our program for the day. I think on the whole we have had a very successful 
meeting. 
It has been a source of regret that the shipbuilding interests usually represented here by 
so many of their number have been rather sparsely represented at this meeting and that only 
a few have been present. Of course, you who have read the papers know the reason; you know 
that there is a conference in Washington which has kept so many of them away from the 
meeting, which is a source of great regret to many of us. 
I desire to remind you of the banquet to-night. Those who have not received tickets 
should apply to the Secretary or his assistant. There is every prospect that the banquet will 
be the greatest one, so far as attendance goes, that the Society has ever held. I understand 
