374 Mr. Gill on the Patent Self -existing Engine. [Nov. 



since exploded doctrine of attraction and repulsion, and with 

 considerable force, and says that he has in the country a machine 

 of two horses' power. On being asked if he had any pieces of 

 the compound metals with him besides those on the machine, 

 he said he had not, and would not suffer any person to possess 

 them, lest they should take them to pieces, and thereby discover 

 their composition. On being questioned as to his patent, he 

 said that in fact he had none, having merely entered a caveat ta 

 prevent any persons from taking out a patent for a similar 

 machine without his being informed thereof. So much then for 

 his pretended patent ; and I verily beheve that his new invented 

 power rests on no better a foundation ; and that in fact his 

 ■wheel is turned by a spring mounted on a barrel, as usual in 

 spring clocks, and other pieces of mechanism, and which is 

 concealed, either in the substance of the table itself, or in the 

 thick pillar which supports it, the barrel having a ring of teeth 

 around it, working in a pinion, affixed upon the lower end of an 

 upright axis concealed in one of the brass columns that support 

 the horizontal axis of the wheel, and having at its upper end 

 another pinion which works into a small toothed contrate wheel 

 fixed on the end of the horizontal axis, but also concealed in the 

 brass block on the top of the column, and in another pillar 

 which is screwed upon the top of the block, and is quite large 

 enough to contain it, and thus gives motion to the wheel, and 

 indeed the artifice is but very clumsily concealed. I should 

 have added that the brass pillar last mentioned supports an 

 upright axis having a pinion at its lower end, which is driven by 

 a contrate wheel on the horizontal axis of the wheel, and which 

 upright axis has at the top of it a fly with wings to regulate the 

 motion of the machine, as in other spring movements. 



This barefaced imposition reminds me of another which was 

 practised upon the public several years since, and was detected, 

 and very properly exposed, by my friend Mr. J. T. Hawkins, 

 which put an end to the trick : this consisted of what was said 

 to be a self-moving pendulum, and beneath the ball of it a bottle 

 was placed, out of which, as the exhibitor pretended, an elastic 

 fluid was continually proceeding, which gave an impulse to the 

 ball as it passed over it. Mr. Hawkins, however, found that the 

 impulse was in fact given to the pendulum at its upper end ; and 

 that the axis on which it hung communicated with another pen- 

 dulum which was kept in motion by a weight or other maintain- 

 ing power ; for in like manner the real cause of the wheel's motion 

 in this new imposition is concealed ; and the attention of the 

 spectator is directed to another pretended first mover, and 

 which is besides attended with the additional advantage of 

 affording him matter for wonder, which constitutes the chief 

 pleasure of the multitude, and contributes greatly to the profit of 

 the exhibition. I am, Sir, your most obedient servant, 



Thomas Gill. 



