PERPETUAL MOTION 71 



Mr. Dircks, in his " Perpetuum Mobile," has given ac- 

 counts of quite a number of these impostures. The fol- 

 lowing are some of the most notable : 



M. Poppe of Tubingen tells of a clock made by M. Geiser, 

 which was an admirable piece of mechanism and seemed to 

 have solved this great problem in an ingenious and simple 

 manner, but it deceived only for a time. When thoroughly 

 examined inwardly and outwardly, some time after his 

 death, it was found that the center props supporting its 

 cylinders contained cleverly constructed, hidden clock-work, 

 wound up by inserting a key in a small hole under the sec- 

 ond-hand. 



Another case was that of a man named Adams who ex- 

 hibited, for eight or nine days, his pretended perpetual 

 motion in a town in England and took in the natives for 

 fifty or sixty pounds. Accident, however, led to a discov- 

 ery of the imposture. A gentleman, viewing the machine 

 took hold of the wheel or trundle and lifted it up a little, 

 which probably disengaged the wheels that connected the 

 hidden machinery in the plinth, and immediately he heard 

 a sound similar to that of a watch when the spring is run- 

 ning down. The owner was in great anger and directly 

 put the wheel into its proper position, and the machine 

 again went around as before. The circumstance was men- 

 tioned to an intelligent person who determined to find out 

 and expose the imposture. He took with him a friend to 

 view the machine and they seated themselves one on each 

 side of the table upon which the machine was placed. 

 They then took hold of the wheel and trundle and lifted 

 them up, there being some play in the pivots. " Immedi- 

 ately the hidden spring began to run down and they con- 

 tinued to hold the machine in spite of the endeavors of 



