WITH NOTES. 455 



And if we reverse the motion of the wheel, turning it 

 from the right hand to the left hand, we shall reverse 

 these positions also, (the lower end of the cord sliding 

 in a groove towards a left hand spoke) but without the 

 wheel having any tendency to move of itself. 



His notice of this exhibition was not written by the 

 Marquis until 1655, from 14 to 17 years after its occur 

 rence, and he may have then hesitated to say that it 

 was not a success ; but he may have persuaded himself 

 that he was at last in possession of the secret that was 

 at first wanting. Besides, we are not to infer that the 

 company described as being present had gone to the 

 Tower purposely to see the Marquis s wheel ; it being 

 far more probable that, Charles the First and the 

 foreign ambassadors were there to view that fortress 

 with all its treasures and curiosities. 



According to the state of knowledge in 1663, the 

 Marquis of Worcester was not singular in entertaining 

 this subject, and all we can make of the present article 

 is, that he has left it open to doubt whether he himself 

 did not consider that his experiment required con 

 firmation. &quot; Perpetuum Mobile ; or a history of the 

 search for self-motive power,&quot; 1862, is a work which 

 may be taken as an elaborate note on this article, for 

 it was the perusal of it that led the author, to com 

 mence the compilation of that work, more than thirty 

 years ago. 



Before the publication of the &quot; Century &quot; Samuel 

 Hartlib had, (on the 10th of August, 1658,) written to 

 Mr. Boyle on the subject of a perpetual motion invented 

 by the ingenious and celebrated John Joachim Becher, 

 an account of which was to be printed at Frankfort. 

 Boyle s Works, fol. 1744, p. 280. 



Charles the Second was favoured with the exhibition 

 of another scheme of this sort, by John Evelyn, a 



