Perpetual Motion 73 



from the liquefying plant which it works, thus leaving seven pints, 

 at no cost, to drive another engine doing useful work. 



"This almost takes your breath away," says the interviewer, 

 "but this, you remark, is perpetual motion." "No," says Mr. 

 Tripler, sharply, " no perpetual motion about it. The heat of the 

 atmosi)here is boiling the liquid air in my engine and producing 

 power just as the heat of coal boils water and drives off the steam, 

 I simply use another form of heat ; I get my power from the sun 

 — the perpetual motion crank tries to use the attraction of gravita- 

 tion, not the heat of the sun." Then the interviewer raphsodises, 

 " It is bewildering to dream of the possibilities of a source of 

 power that costs nothing. Think of the ocean greyhound unen- 

 cumbered with coal bunkers and sweltering boilers and smoke- 

 stacks, making her power as she sails from the free ocean air 

 around her." 



Alas ! whatever may have been the source of I'ripler's self- 

 deception, the invention never materialised, and it is certain Mr. 

 Tripler was as much of a "perpetual motion crank" as the gravi- 

 tation theorists he mentions. 



But some attention must now be paid to devices intended 

 to utilize the power of permanent magnets. 



Many such inventions have been proposed, the form often 

 being that of a wheel having slightly projecting steel studs upon 

 its circumference, intended to come under the influence of per- 

 manent magnets and to be shielded from this influence by auto- 

 matically inserting a small sheet of some insulating material at the 

 proper moment to release the pull upon a particular stud and thus 

 transfer the action to the next in rotation.. A figure representing 

 such a wheel can be studied in the ^^Encyclopaedia Britannica" 

 where also it is pointed out that a stationary shield, should such 

 be possible, would serve the same purpose. It is apparent from 

 modern theories of energy that the use of such an automatic 

 shield, were such a substance possible, could only result in one of 

 two ways. Either the power needed to place such a shield in 

 position would be equal to that due to the permanent magnet, or 

 the rotation of the wheel would rapidly result in the demagnetism 



