MIRACLES OF SCIENCE 



tus through which the force is manifested is intrins- 

 ically nothing more mysterious than a spinning top. 

 The principle involved is that of gyroscopic action. 

 Some one has said that the spinning top is the play- 

 thing of children and the marvel of sages. The first 

 proposition expresses a familiar truth; the force of 

 the second will become increasingly manifest as we 

 pass in review some wonderful applications to which 

 the gyroscope has been put in very recent years, one 

 of which has just been suggested. We shall see pres- 

 ently that the same mysterious yet in a sense quite 

 explicable force which supplies us with a perfected 

 compass gives us also an apparatus that will prevent a 

 ship from rolling at sea; an allied apparatus that will 

 balance a railway car on a single rail; and yet another 

 apparatus that will stabilize an aeroplane, holding 

 that craft on an even keel in the midst of tempests 

 and fluctuating air currents, with a facility far sur- 

 passing the most dexterous efforts of the most accom- 

 plished human aviator. 



There are other minor feats of stabilizing also 

 which we shall find not without interest; but these 

 three major ones suffice to establish the gyroscope 

 as one of the most wonderful of devices. The results 

 of its operation seem weird to the point almost of in- 

 credibility. Yet the principle on which it operates 

 is fully exemplified in the action of the spinning top 

 with which every child plays. Modified tops, ingen- 

 iously suspended, may perform not only all the feats 

 just outlined, but may tangibly demonstrate the fact 

 of the earth's rotation. The latter feat was accom- 

 plished more than half a century ago by the famous 



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