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THE NATIONAL GEOGRAPHIC MAGAZINE 



d-i 



A NATIVE TYPD : TRANSCAUCASIA 



"because the earth is not flat, but round. 

 The ordinary mariner would not find it 

 ■easy to determine and check up on these 

 •errors. 



Hence the gyroscope compass, while a 

 most useful and ingenious invention, 

 also has its limitations, and will not at 

 present answer the requirements for con- 

 tinual and universal use. Thus we are 

 again brought face to face with the 

 necessity of making a most careful study 

 ■of that which the Supreme Architect has 

 ^iven us — the earth's magnetism. 



w^HY DO the; magnejtic poles move? 



I trust the why and wherefore of the 

 magnetic work of the Carnegie Institu- 

 tion of Washington has now been made 

 clear : To make the most complete study 

 possible of the earth's magnetic forces, 

 both as regards their direction and their 

 strength, and, having done this, to deter- 

 mine the changes forever going on, in 

 order that magnetic charts may be kept 

 up to date for the use of the navigator, 

 the surveyor, the explorer, and the man 

 of science. 



Thus far only the purely practical and 

 sordid side of a "Magnetic Survey of the 

 Earth" has been presented, but, happily, 

 man will not thus be contented ; he wants 

 to know, not simply the "how," but the 

 "why" as well. The many intelligent 

 questions received at the office in Wash- 

 ington and those put to us by persons of 

 all walks of life who visit the Carnegie, 

 when in port, must be taken as evidence 

 of genuine interest. I question whether 

 ever before so many people the world 

 over have been led to inquire, What is 

 "terrestrial magnetism," anyway? To 

 be sure, some of the letters are addressed 

 to the "Department of Celestial Magnet- 

 ism," or to the "Department of Terres- 

 trial Rheumatism," etc. In the main the 

 questions asked are : Where is the Mag- 

 netic North Pole ? Does it move, or is it 

 fixed? If it moves, is this the reason 

 why the compass changes _ its direction 

 from year to year? What makes the 

 magnetic poles move? What is the 

 cause of magnetic storms, and what is 

 their connection with auroral lights, elec- 

 tric currents in the earth, and sun spots? 



Eor most of these queries the data are 

 at present either lacking or not sufficient 

 to give definite and complete answers. 



THE NON-MAGNETIC YACHT "caRNEGIE" 



Now to return to the clipping quoted 

 in our opening paragraph. First of all, 

 let me correct a popular misapprehen- 

 sion : the Carnegie is in no wise either 

 owned or controlled by Mr Andrew 

 Carnegie. To him, however, who has 

 acquired his wealth from the successful 



