THE WORLD'S ADVANCE 



257 



Collisions in fog may also be avoided 

 through ascertaining the presence of an- 

 other vessel by a regularly repeated sig- 

 nal. The direction determined, the in- 

 creasing strength of the signals would 

 indicate that the other ship was approach- 

 ing and the course could be slightly al- 

 tered to avoid her. Any question as to 

 whether the ship was approaching on the 

 port bow or overhauling on the star- 

 board quarter could be determined if the 

 navigator cared to, by the wireless oper- 

 ator sending a query addressed to the 

 other ship. 



distress call alone would be sufficient for 

 the direction finder to give to the captain 

 of the rescuing vessel the direction to 

 take through the thickest blanket of fog. 

 Once turned in the direction given by the 

 pointer a straight course would bring the 

 relief vessel to the scene of the disaster 

 in the shortest possible time. What a 

 few minutes lost in blindly groping 

 through the fog means is best appre- 

 ciated by a mental picture of hundreds of 





Three Main Pieces of Apparatus in Direction Finder System: 

 Above Interior View of the Goniometer; In the Oval The 

 Angle Divider; At the Right The Goniometer Coils, Show- 

 ing the Exploring Coil Rotating on the Shaft of the Indicator. 



In the avoidance of collisions at sea 

 the direction finder has a field of incal- 

 culable value. So also in rescue work 

 is it of the greatest assistance. It will 

 be remembered that when the heavily 

 laden steamship Monroe received her 

 death blow off the Virginia coast she 

 sank so quickly that there was no time 

 for the wireless operator to send out the 

 ship's position. In such emergencies the 



is 



struggling humans striving to keep afloat 

 in the icy waters of midwinter. 



The accuracy of the instrument 

 surprising in view of the fact that Mar- 

 coni claims for it a possible error in tak- 

 ing bearings of two to three degrees, and 

 under the most unfavorable conditions 

 not in excess of five degrees. Tests made 

 along the Atlantic on the steamship 

 Northland checked absolutely with the 



