Popular Science Monthly 



843 



D R c 



Electron- 



Magnetizing Steel Without 

 Using a Lodestone 



S. J. BARNETT, of Ohio State 

 University, has recently discovered an 

 entirely new method of 

 producing magnetism — the ~£ 



first since the finding of the ***' 



lodestone or natural mag- 

 net in ancient times, by /' 

 means of which a magnetic 

 field was produced in which 

 the body to be magnetized 

 was placed. Dr. Barnett, 

 however, has been able to 

 produce magnetism with- 

 out the influence of any 

 outside agency, by simply 

 rotating a piece of steel at a 

 speed of about forty-five 

 revolutions per second. 

 Perhaps this fact may 

 help in the final solution 

 of the great problem of the 

 earth's magnetism which 

 scientists for ages. 



If a bar of steel can be magnetized by 

 rotating it, why can't the earth produce its 

 magnetism in the same way, as it rotates 

 upon its axis? 



In the first place he has found that a bar 

 of steel behaves just as if its molecules were 

 little spinning tops, or rather minute 

 gyroscopes. These gyroscopic molecules 

 line up with their axes parallel to the axis 

 of rotation of the bar, and 

 because each molecule acts 

 as a magnet the whole bar 

 then becomes magnetized. 



The reason why the 

 molecules act as they do 

 has been very carefully 

 worked out and the result 

 seems to substantiate the 

 now common electrical 

 theory of matter. This 

 theory assumes that each 

 atom of matter consists of 

 a positive center about 

 which a little negatively 

 charged particle is rotating 

 at very high speed. From 

 this it is deduced that 

 each atom is a minute gy- 

 roscope and that the nega- 

 tive particle rotating about 

 its axis acts just exactly 

 like, an electric current 

 and magnetizes the atom. 



•Nucleus 



T 



in the electrical theory of 

 matter, each atom is a nega- 

 tively charged particle revolv- 

 ing about a positive center 



has puzzled 



"Hand Over Your Watch!" Why 

 Certainly, Mr. Burglar 



WITH a revolver disguised as a harm- 

 less watch, Leonard Woods, of St. 

 Louis, Missouri, hopes tc 

 rn*_ get the ''drop" on a burglar 



> "**v,.. who has the drop on him. 



When he has been asked to 

 \ hand over his watch he will 



willingly pretend to do so, 

 \ but he will deliver a volley 

 of hot lead instead. 



The device is really a 

 seven-shooter with a re- 

 peating mechanism small 

 enough to fit in the limited 

 space of an ordinary watch- 

 case. The encompassing 

 of all the mechanism in 

 such a space is a real 

 achievement. It took 

 Woods several years to do 

 it. The manner in which 

 he finally accomplished it is shown by the 

 accompanying illustration. 



The barrel of the revolver is the watch 

 stem hollowed out. The trigger, which 

 slides along on this stem, is placed in such a 

 position that your forefinger naturally en- 

 circles it when you are compelled to take 

 the watch from your pocket. As you pre- 

 tend to be looking at the time, you arc 

 actually aiming at the hard heart in front 

 of you. If the thief insists upon having the 

 use of your watch, you car, 

 give it to him by simpl) 

 pressing the trigger. When 

 that is pressed in, the cart- 

 ridge cylinder will be turn- 

 ed around and the hammer 

 will be brought back until 

 a. cartridge is in line with 

 the barrel and the hammer 

 is automatically released. 



The barrel of the seven- shoot- 

 er watch-revolver is the hol- 

 lowed out watch stem. The 

 trigger slides along this stem 



Cyl'nder pawl 



