ON THE INTERACTION OF NATURAL FORCES. 147 



Now could not the heat generated by the plates be applied to a 

 small steam-engine, which in its turn should be able to keep 

 the rubbing plates in motion 1 The perpetual motion would 

 thus be at length found. This question might be asked, and 

 could not be decided by the older mathematico-mechanical 

 investigations. I will remark beforehand, that the general 

 law which I will lay before you answers the question in the 

 negative. 



By a similar plan, however, a speculative American set 

 some time ago the industrial world of Europe in excitement. 

 The magneto-electric machines often made use of in the case of 

 rheumatic disorders are well known to the public. By impart- 

 ing a swift rotation to the magnet of such a machine we obtain 

 powerful currents of electricity. If those be conducted through 

 water, the latter will be resolved into its two components, 

 oxygen and hydrogen. By the combustion of hydrogen, water 

 is again generated. If this combustion takes place, not in 

 atmospheric air, of which oxygen only constitutes a fifth part, 

 but in pure oxygen, and if a bit of chalk be placed in the flame, 

 the chalk will be raised to its white heat, and give us the sun- 

 like Drummond's light. At the same time the flame developes a 

 considerable quantity of heat. Our American proposed to utilise 

 in this way the gases obtained from electrolytic decomposition, 

 and asserted, that by the combustion a sufficient amount of 

 heat was generated to keep a small steam-engine in action, 

 which again drove his magneto-electric machine, decomposed the 

 water, and thus continually prepared its own fuel. This would 

 certainly have been the most splendid of all discoveries; a 

 perpetual motion which, besides the force that kept it going, 

 generated light like the sun, and warmed all around it. The 

 matter was by no means badly thought out. Each practical 

 step in the affair was known to be possible ; but those who at 

 that time were acquainted with the physical investigations 

 which bear upon this subject, could have affirmed, on first 

 hearing the report, that the matter was to be numbered among 

 the numerous stories of the fable-rich America ; and indeed a 

 fable it remained. 



